diff --git a/README.md b/README.md
index fde8c79..eee687e 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ The following requirements must be set up before installing Chargebee’s Androi
 The `Chargebee-Android` SDK can be installed by adding below dependency to the `build.gradle` file:
 
 ```kotlin
-implementation 'com.chargebee:chargebee-android:1.0.8'
+implementation 'com.chargebee:chargebee-android:1.0.9'
 ```
 
 ## Example project
@@ -347,7 +347,7 @@ Chargebee is available under the [MIT license](https://opensource.org/licenses/M
   To install Chargebee's Android SDK, add the following dependency to the build.gradle file.
   
   ```
-  implementation 'com.chargebee:chargebee-android:1.0.8'
+  implementation 'com.chargebee:chargebee-android:1.0.9'
   ```
   Example project
   ---------------
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 89f51ce..36a7f0b 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -22,6 +22,7 @@
         <activity android:name=".items.ItemActivity"/>
         <activity android:name=".plan.PlansActivity"/>
         <activity android:name=".subscription.SubscriptionActivity"/>
+        <activity android:name=".plan.UpgradePlanActivity"/>
         <activity android:name="com.chargebee.example.MainActivity">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
diff --git a/app/src/main/java/com/chargebee/example/MainActivity.kt b/app/src/main/java/com/chargebee/example/MainActivity.kt
index 87700ba..ba2a8f8 100644
--- a/app/src/main/java/com/chargebee/example/MainActivity.kt
+++ b/app/src/main/java/com/chargebee/example/MainActivity.kt
@@ -27,6 +27,8 @@ import com.chargebee.example.items.ItemActivity
 import com.chargebee.example.items.ItemsActivity
 import com.chargebee.example.plan.PlanInJavaActivity
 import com.chargebee.example.plan.PlansActivity
+import com.chargebee.example.plan.UpgradePlanActivity
+import com.chargebee.example.util.Constants.PRICE_KEY
 import com.chargebee.example.subscription.SubscriptionActivity
 import com.chargebee.example.token.TokenizeActivity
 import com.chargebee.example.util.CBMenu
@@ -124,6 +126,15 @@ class MainActivity : BaseActivity(), ListItemsAdapter.ItemClickListener {
                 val intent = Intent(this, SubscriptionActivity::class.java)
                 startActivity(intent)
             }
+            CBMenu.UpgradePlan.value -> {
+                val intent = Intent(this, UpgradePlanActivity::class.java)
+                startActivity(intent)
+            }
+            CBMenu.PriceChange.value -> {
+                val intent = Intent(this, UpgradePlanActivity::class.java)
+                intent.putExtra(PRICE_KEY, "priceChange")
+                startActivity(intent)
+            }
             else ->{
                 Log.i(javaClass.simpleName, " Not implemented" )
             }
diff --git a/app/src/main/java/com/chargebee/example/billing/BillingViewModel.kt b/app/src/main/java/com/chargebee/example/billing/BillingViewModel.kt
index f175266..f48a647 100644
--- a/app/src/main/java/com/chargebee/example/billing/BillingViewModel.kt
+++ b/app/src/main/java/com/chargebee/example/billing/BillingViewModel.kt
@@ -1,5 +1,6 @@
 package com.chargebee.example.billing
 
+import android.content.Context
 import android.util.Log
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
@@ -25,6 +26,8 @@ class BillingViewModel : ViewModel() {
     var subscriptionList: MutableLiveData<ArrayList<SubscriptionDetailsWrapper>?> = MutableLiveData()
     var error: MutableLiveData<String?> = MutableLiveData()
     private var subscriptionId: String = ""
+    var updateProductPurchaseResult: MutableLiveData<String> = MutableLiveData()
+    var priceChangeLiveData: MutableLiveData<String> = MutableLiveData()
 
     fun purchaseProduct(product: CBProduct, customerID: String) {
 
@@ -102,4 +105,80 @@ class BillingViewModel : ViewModel() {
             }
         }
     }
+
+    fun updatePurchase(productIdList: ArrayList<String>, oldPurchaseToken: String, context: Context){
+        CBPurchase.retrieveProducts(context,
+            productIdList,object : CBCallback.ListProductsCallback<ArrayList<CBProduct>>{
+                override fun onSuccess(productIDs: ArrayList<CBProduct>) {
+                    if (productIDs.size > 0) {
+                        CBPurchase.updateProduct(context, productIDs.first(),oldPurchaseToken, object : CBCallback.PurchaseCallback<String>{
+                            override fun onSuccess(purchaseToken: String, status:Boolean) {
+                                Log.i(TAG, "purchaseToken:  $purchaseToken")
+                                updateProductPurchaseResult.postValue(purchaseToken)
+                            }
+                            override fun onError(error: CBException) {
+                                try {
+                                    cbException.postValue(error.message)
+                                }catch (exp: Exception){
+                                    Log.i(TAG, "Exception :${exp.message}")
+                                }
+                            }
+
+                        })
+                    } else {
+                        Log.i(javaClass.simpleName,"Product id not found in Google Play")
+                        cbException.postValue("Product id not found in Google Play")
+                    }
+                }
+
+                override fun onError(error: CBException) {
+                    Log.e(javaClass.simpleName, "Error:  ${error.message}")
+                    try {
+                        cbException.postValue(error.message)
+                    }catch (exp: Exception){
+                        Log.e(TAG, "Exception :${exp.message}")
+                    }
+                }
+
+            })
+
+    }
+
+    fun priceChangeUpdate(productIdList: ArrayList<String>, context: Context){
+        CBPurchase.retrieveProducts(
+            context,
+            productIdList,
+            object : CBCallback.ListProductsCallback<ArrayList<CBProduct>> {
+                override fun onSuccess(productIDs: ArrayList<CBProduct>) {
+                        if (productIDs.size > 0) {
+                            CBPurchase.priceChangeConfirmation(productIDs.first(), object: CBCallback.PriceChangeCallback<String>{
+                                override fun onSuccess(response: String) {
+                                    priceChangeLiveData.postValue(response)
+                                }
+
+                                override fun onError(error: CBException) {
+                                    Log.e(javaClass.simpleName,"Error in Price Change: ${error.message}")
+                                    try {
+                                        cbException.postValue(error.message)
+                                    }catch (exp: Exception){
+                                        Log.i(TAG, "Exception :${exp.message}")
+                                    }
+                                }
+
+                            })
+                        } else {
+                            Log.i(javaClass.simpleName,"Product id not found in Google Play")
+                            cbException.postValue("Product id not found in Google Play")
+                        }
+                }
+                override fun onError(error: CBException) {
+                    Log.e(javaClass.simpleName, "Error:  ${error.message}")
+                    try {
+                        cbException.postValue(error.message)
+                    }catch (exp: Exception){
+                        Log.e(TAG, "Exception :${exp.message}")
+                    }
+                }
+            })
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/chargebee/example/plan/UpgradePlanActivity.kt b/app/src/main/java/com/chargebee/example/plan/UpgradePlanActivity.kt
new file mode 100644
index 0000000..165c521
--- /dev/null
+++ b/app/src/main/java/com/chargebee/example/plan/UpgradePlanActivity.kt
@@ -0,0 +1,88 @@
+package com.chargebee.example.plan
+
+import android.content.Context
+import android.os.Bundle
+import android.text.TextUtils
+import android.util.Log
+import android.view.View
+import android.widget.Button
+import android.widget.TextView
+import androidx.lifecycle.Observer
+import com.chargebee.example.BaseActivity
+import com.chargebee.example.R
+import com.chargebee.example.billing.BillingActivity
+import com.chargebee.example.billing.BillingViewModel
+import com.chargebee.example.util.Constants
+import com.google.android.material.textfield.TextInputEditText
+import com.google.android.material.textfield.TextInputLayout
+
+class UpgradePlanActivity : BaseActivity() {
+
+    private var mBillingViewModel : BillingViewModel? = null
+    private lateinit var mProductIdInput: TextInputEditText
+    private lateinit var mPurchaseTokenInput: TextInputEditText
+    private lateinit var mBuyProductButton: Button
+    private lateinit var mPriceChangeButton: Button
+    private lateinit var mPurchaseTokenInputLayout: TextInputLayout
+    private lateinit var mTvPriceChange: TextView
+    lateinit var context: Context
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_upgradeplan)
+        context = this
+        mBillingViewModel = BillingViewModel()
+        mProductIdInput = findViewById(R.id.productIdInput)
+        mPurchaseTokenInput = findViewById(R.id.purchaseTokenInput)
+        mBuyProductButton = findViewById(R.id.buyBtn)
+        mPriceChangeButton = findViewById(R.id.btnpricechange)
+        mPurchaseTokenInputLayout = findViewById(R.id.purchaseTokenInputLayout)
+        mTvPriceChange = findViewById(R.id.textView)
+
+        val priceChange = intent.getStringExtra(Constants.PRICE_KEY)
+        if(priceChange !=null){
+            mPurchaseTokenInputLayout.visibility = View.GONE
+            mBuyProductButton.visibility = View.GONE
+            mTvPriceChange.text = "Plan Price Change"
+
+        }else{
+            mPurchaseTokenInputLayout.visibility = View.VISIBLE
+            mPriceChangeButton.visibility = View.GONE
+            mTvPriceChange.text = "Plan Upgrade/Downgrade"
+
+        }
+
+        this.mBillingViewModel!!.updateProductPurchaseResult.observeForever{
+            hideProgressDialog()
+            if (!TextUtils.isEmpty(it))
+            alertSuccess(it)
+        }
+
+        this.mBillingViewModel!!.priceChangeLiveData.observeForever{
+            hideProgressDialog()
+            if (!TextUtils.isEmpty(it))
+                alertSuccess(it)
+        }
+        this.mBillingViewModel!!.cbException.observeForever{
+            if (!TextUtils.isEmpty(it))
+                alertSuccess(it)
+        }
+
+        mBuyProductButton.setOnClickListener{
+            var productId = mProductIdInput.text.toString()
+            val purchaseToken = mPurchaseTokenInput.text.toString()
+
+            val array = arrayListOf<String>(productId)
+            this.mBillingViewModel!!.updatePurchase(array, purchaseToken, context)
+        }
+
+        mPriceChangeButton.setOnClickListener{
+            var productId = mProductIdInput.text.toString()
+            val productIdList =  ArrayList<String>()
+            productIdList.add(productId)
+            this.mBillingViewModel!!.priceChangeUpdate(productIdList, context)
+
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/chargebee/example/util/CBMenu.kt b/app/src/main/java/com/chargebee/example/util/CBMenu.kt
index 630d5f5..cc3ed1e 100644
--- a/app/src/main/java/com/chargebee/example/util/CBMenu.kt
+++ b/app/src/main/java/com/chargebee/example/util/CBMenu.kt
@@ -11,6 +11,8 @@ enum class CBMenu(val value: String) {
     ProductIDs("Get Google Play Product Identifiers"),
     GetProducts("Get Products"),
     SubsStatus("Get Subscription Status"),
-    SubsList("Get Subscriptions List")
+    SubsList("Get Subscriptions List"),
+    UpgradePlan("Upgrade/Downgrade Plan"),
+    PriceChange("Price Change")
 }
 
diff --git a/app/src/main/java/com/chargebee/example/util/Constants.kt b/app/src/main/java/com/chargebee/example/util/Constants.kt
index 700be5d..01f4dbe 100644
--- a/app/src/main/java/com/chargebee/example/util/Constants.kt
+++ b/app/src/main/java/com/chargebee/example/util/Constants.kt
@@ -2,4 +2,5 @@ package com.chargebee.example.util
 
 object Constants {
     const val PRODUCTS_LIST_KEY = "products"
+    const val PRICE_KEY = "priceChange"
 }
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_upgradeplan.xml b/app/src/main/res/layout/activity_upgradeplan.xml
new file mode 100644
index 0000000..ecf3901
--- /dev/null
+++ b/app/src/main/res/layout/activity_upgradeplan.xml
@@ -0,0 +1,78 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".plan.UpgradePlanActivity">
+
+    <com.google.android.material.textfield.TextInputLayout
+        android:id="@+id/productInputLayout"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="40dp"
+        android:hint="Product ID"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.497"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/textView">
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/productIdInput"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:ems="15"
+            android:inputType="textPersonName"
+            android:text="" />
+    </com.google.android.material.textfield.TextInputLayout>
+    <com.google.android.material.textfield.TextInputLayout
+        android:id="@+id/purchaseTokenInputLayout"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="40dp"
+        android:hint="Purchase Token"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.497"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/productInputLayout">
+        <com.google.android.material.textfield.TextInputEditText
+            android:id="@+id/purchaseTokenInput"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:ems="15"
+            android:inputType="textPersonName"
+            android:text="" />
+    </com.google.android.material.textfield.TextInputLayout>
+    <TextView
+        android:id="@+id/textView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="48dp"
+        android:text="Plan Upgrade/Downgrade"
+        android:textSize="24sp"
+        android:textStyle="bold"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
+    <Button
+        android:id="@+id/buyBtn"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="32dp"
+        android:text="Change Plan"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.497"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/purchaseTokenInputLayout" />
+    <Button
+        android:id="@+id/btnpricechange"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="32dp"
+        android:text="Price Change"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintHorizontal_bias="0.497"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/buyBtn" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/chargebee/build.gradle b/chargebee/build.gradle
index 2077b11..f8407f0 100644
--- a/chargebee/build.gradle
+++ b/chargebee/build.gradle
@@ -9,7 +9,7 @@ android {
         minSdkVersion 21
         targetSdkVersion 30
         versionCode 1
-        versionName "1.0.8"
+        versionName "1.0.9"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         consumerProguardFiles "consumer-rules.pro"
diff --git a/chargebee/src/main/java/com/chargebee/android/billingservice/BillingClientManager.kt b/chargebee/src/main/java/com/chargebee/android/billingservice/BillingClientManager.kt
index 33227de..e3b6ad7 100644
--- a/chargebee/src/main/java/com/chargebee/android/billingservice/BillingClientManager.kt
+++ b/chargebee/src/main/java/com/chargebee/android/billingservice/BillingClientManager.kt
@@ -7,6 +7,7 @@ import android.os.Looper
 import android.text.TextUtils
 import android.util.Log
 import com.android.billingclient.api.*
+import com.android.billingclient.api.BillingClient.BillingResponseCode.*
 import com.chargebee.android.ErrorDetail
 import com.chargebee.android.exceptions.CBException
 import com.chargebee.android.exceptions.ChargebeeResult
@@ -28,9 +29,11 @@ class BillingClientManager constructor(
     private var callBack : CBCallback.ListProductsCallback<ArrayList<CBProduct>>
     private var purchaseCallBack: CBCallback.PurchaseCallback<String>? = null
     private val skusWithSkuDetails = arrayListOf<CBProduct>()
-    private val TAG = "BillingClientManager"
+    private val TAG = javaClass.simpleName
     var customerID : String = ""
     lateinit var product: CBProduct
+    var oldPurchaseToken: String? = null
+    lateinit var newSkuDetails: SkuDetails
 
     init {
         mContext = context
@@ -52,7 +55,7 @@ class BillingClientManager constructor(
             BillingClient.BillingResponseCode.OK -> {
                 Log.i(
                     TAG,
-                    "onBillingSetupFinished() -> successfully for ${billingClient.toString()}."
+                    "Google Billing Setup Done!"
                 )
                 loadProductDetails(BillingClient.SkuType.SUBS, skuList, callBack)
             }
@@ -79,7 +82,6 @@ class BillingClientManager constructor(
                     TAG,
                     "onBillingSetupFinished() -> Client is already in the process of connecting to billing service"
                 )
-
             }
             else -> {
                 Log.i(TAG, "onBillingSetupFinished -> with error: ${billingResult.debugMessage}.")
@@ -119,7 +121,7 @@ class BillingClientManager constructor(
                .setType(skuType)
                .build()
 
-           queryAllPurchases()
+           // queryAllPurchases()
 
            billingClient.querySkuDetailsAsync(
                params
@@ -140,7 +142,7 @@ class BillingClientManager constructor(
                        Log.i(TAG, "Product details :$skusWithSkuDetails")
                        callBack.onSuccess(productIDs = skusWithSkuDetails)
                    }catch (ex: CBException){
-                       callBack.onError(CBException(ErrorDetail(GPErrorCode.UnknownError.errorMsg)))
+                       callBack.onError(CBException(ErrorDetail(billingResult.debugMessage)))
                        Log.e(TAG, "exception :" + ex.message)
                    }
                }else{
@@ -152,7 +154,6 @@ class BillingClientManager constructor(
            Log.e(TAG, "exception :$exp.message")
            callBack.onError(CBException(ErrorDetail("${exp.message}")))
        }
-
     }
 
     /* Purchase the product: Initiates the billing flow for an In-app-purchase  */
@@ -176,8 +177,8 @@ class BillingClientManager constructor(
             .takeIf { billingResult -> billingResult.responseCode != BillingClient.BillingResponseCode.OK
             }?.let { billingResult ->
                 Log.e(TAG, "Failed to launch billing flow $billingResult")
+                purchaseCallBack.onError(CBException(ErrorDetail(GPErrorCode.LaunchBillingFlowError.errorMsg)))
             }
-
     }
 
     /* Checks if the specified feature is supported by the Play Store */
@@ -206,7 +207,7 @@ class BillingClientManager constructor(
     /* Google Play calls this method to deliver the result of the Purchase Process/Operation */
     override fun onPurchasesUpdated(billingResult: BillingResult, purchases: MutableList<Purchase>?) {
         when (billingResult.responseCode) {
-            BillingClient.BillingResponseCode.OK -> {
+            OK -> {
                 purchases?.forEach { purchase ->
                     when (purchase.purchaseState) {
                         Purchase.PurchaseState.PURCHASED -> {
@@ -221,29 +222,41 @@ class BillingClientManager constructor(
                     }
                 }
             }
-            BillingClient.BillingResponseCode.ITEM_ALREADY_OWNED -> {
-                Log.e(TAG, "onPurchasesUpdated: ITEM_ALREADY_OWNED")
+            ITEM_ALREADY_OWNED -> {
+                Log.e(TAG, "Billing response code : ITEM_ALREADY_OWNED")
                 purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.ProductAlreadyOwned.errorMsg)))
             }
-            BillingClient.BillingResponseCode.SERVICE_DISCONNECTED -> {
+            SERVICE_DISCONNECTED -> {
                 connectToBillingService()
             }
-            BillingClient.BillingResponseCode.ITEM_UNAVAILABLE -> {
-                Log.e(TAG, "onPurchasesUpdated: ITEM_UNAVAILABLE")
+            ITEM_UNAVAILABLE -> {
+                Log.e(TAG, "Billing response code : ITEM_UNAVAILABLE")
                 purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.ProductUnavailable.errorMsg)))
             }
-            BillingClient.BillingResponseCode.USER_CANCELED ->{
-                Log.e(TAG, "onPurchasesUpdated : USER_CANCELED ")
+            USER_CANCELED ->{
+                Log.e(TAG, "Billing response code  : USER_CANCELED ")
                 purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.CanceledPurchase.errorMsg)))
             }
-            BillingClient.BillingResponseCode.ITEM_NOT_OWNED ->{
-                Log.e(TAG, "onPurchasesUpdated : ITEM_NOT_OWNED ")
+            ITEM_NOT_OWNED ->{
+                Log.e(TAG, "Billing response code  : ITEM_NOT_OWNED ")
                 purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.ProductNotOwned.errorMsg)))
             }
-            else -> {
-                Log.e(TAG, "Failed to PurchasesUpdated"+billingResult.responseCode)
+            SERVICE_TIMEOUT  -> {
+                Log.e(TAG, "Billing response code :SERVICE_TIMEOUT ")
+                purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.PlayServiceTimeOut.errorMsg)))
+            }
+            SERVICE_UNAVAILABLE  -> {
+                Log.e(TAG, "Billing response code: SERVICE_UNAVAILABLE")
+                purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.PlayServiceUnavailable.errorMsg)))
+            }
+            ERROR  -> {
+                Log.e(TAG, "Billing response code: ERROR")
                 purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.UnknownError.errorMsg)))
             }
+            DEVELOPER_ERROR  -> {
+                Log.e(TAG, "Billing response code: DEVELOPER_ERROR")
+                purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.DeveloperError.errorMsg)))
+            }
         }
     }
 
@@ -264,7 +277,13 @@ class BillingClientManager constructor(
                             Log.i(TAG, "Purchase Token -${purchase.purchaseToken}")
                             billingClient.endConnection()
 
-                            validateReceipt(purchase.purchaseToken, product)
+                            if(TextUtils.isEmpty(oldPurchaseToken) && oldPurchaseToken ==null){
+                                validateReceipt(purchase.purchaseToken, product)
+                            }else{
+                                purchaseCallBack?.onSuccess(purchase.purchaseToken, true)
+                                oldPurchaseToken = null
+                            }
+
                         }
 
                     } catch (ex: CBException) {
@@ -342,4 +361,61 @@ class BillingClientManager constructor(
             }
         }
     }
+    /* Update Purchases on existing plan */
+    fun updatePurchaseFlow(context: Context, skuDetails: SkuDetails, oldPurchaseToken: String, updateCallBack : CBCallback.PurchaseCallback<String>) {
+        Log.i(TAG, "oldPurchaseToken : $oldPurchaseToken")
+        this.purchaseCallBack = updateCallBack
+        this.oldPurchaseToken = oldPurchaseToken
+        val updateParams = oldPurchaseToken.let {
+            BillingFlowParams.SubscriptionUpdateParams.newBuilder()
+                .setOldSkuPurchaseToken(it.trim())
+                .setReplaceSkusProrationMode(BillingFlowParams.ProrationMode.IMMEDIATE_WITH_TIME_PRORATION)
+                .build()
+        }
+
+        val billingFlowParams = updateParams.let {
+            BillingFlowParams.newBuilder()
+                .setSkuDetails(skuDetails)
+                .setSubscriptionUpdateParams(it)
+                .build()
+        }
+        billingClient.launchBillingFlow(mContext as Activity, billingFlowParams)
+            .takeIf { billingResult -> billingResult.responseCode != BillingClient.BillingResponseCode.OK
+            }?.let { billingResult ->
+                Log.e(TAG, "Failed to launch billing flow $billingResult")
+                purchaseCallBack?.onError(CBException(ErrorDetail(GPErrorCode.LaunchBillingFlowError.errorMsg)))
+            }
+
+    }
+    /* This method will handle the Price Change confirmation with Google play */
+    fun priceChangeConfirmationFlow(cbProduct: CBProduct, priceChangeCallBack: CBCallback.PriceChangeCallback<String>){
+        val priceChangeParams = PriceChangeFlowParams.newBuilder()
+            .setSkuDetails(cbProduct.skuDetails)
+            .build()
+        billingClient.launchPriceChangeConfirmationFlow(mContext as Activity, priceChangeParams) {
+                billingResult ->
+            when(billingResult.responseCode){
+                BillingClient.BillingResponseCode.OK ->{
+                    Log.i(TAG, "User has accepted/Confirmed Price change")
+                    Log.i(TAG, billingResult.debugMessage)
+                    if (billingResult.debugMessage.isEmpty())
+                        priceChangeCallBack.onError(CBException(ErrorDetail("Success")))
+                    else
+                        priceChangeCallBack.onError(CBException(ErrorDetail(billingResult.debugMessage)))
+                }
+                BillingClient.BillingResponseCode.USER_CANCELED,
+                BillingClient.BillingResponseCode.SERVICE_DISCONNECTED,
+                BillingClient.BillingResponseCode.SERVICE_TIMEOUT,
+                BillingClient.BillingResponseCode.SERVICE_UNAVAILABLE,
+                BillingClient.BillingResponseCode.DEVELOPER_ERROR,
+                BillingClient.BillingResponseCode.ERROR ->{
+                    if (billingResult.debugMessage.isEmpty())
+                        priceChangeCallBack.onError(CBException(ErrorDetail(GPErrorCode.UnknownError.errorMsg)))
+                    else
+                        priceChangeCallBack.onError(CBException(ErrorDetail(billingResult.debugMessage)))
+                }
+            }
+
+        }
+    }
 }
diff --git a/chargebee/src/main/java/com/chargebee/android/billingservice/CBCallback.kt b/chargebee/src/main/java/com/chargebee/android/billingservice/CBCallback.kt
index 5f05fe3..9826eea 100644
--- a/chargebee/src/main/java/com/chargebee/android/billingservice/CBCallback.kt
+++ b/chargebee/src/main/java/com/chargebee/android/billingservice/CBCallback.kt
@@ -17,4 +17,8 @@ interface CBCallback {
         fun onError(error: CBException)
     }
 
+    interface PriceChangeCallback<T> {
+        fun onSuccess(response: String)
+        fun onError(error: CBException)
+    }
 }
\ No newline at end of file
diff --git a/chargebee/src/main/java/com/chargebee/android/billingservice/CBPurchase.kt b/chargebee/src/main/java/com/chargebee/android/billingservice/CBPurchase.kt
index c1cffa2..7bc23c7 100644
--- a/chargebee/src/main/java/com/chargebee/android/billingservice/CBPurchase.kt
+++ b/chargebee/src/main/java/com/chargebee/android/billingservice/CBPurchase.kt
@@ -45,6 +45,15 @@ object CBPurchase {
             callBack.onError(ex)
         }
     }
+    @JvmStatic
+    fun updateProduct(context: Context, cbProduct: CBProduct,oldPurchaseToken:String, callBack : CBCallback.PurchaseCallback<String> ) {
+        try {
+            billingClientManager?.updatePurchaseFlow(context,cbProduct.skuDetails,oldPurchaseToken, callBack)
+        }catch (ex: CBException){
+            Log.i(javaClass.simpleName, "Exception in updateProduct ")
+            callBack.onError(ex)
+        }
+    }
     /* Buy the product with/without customer Id */
     @JvmStatic
     fun purchaseProduct(
@@ -54,10 +63,14 @@ object CBPurchase {
             CBAuthentication.isSDKKeyValid(Chargebee.sdkKey){
                 when(it){
                     is ChargebeeResult.Success -> {
-                        if (billingClientManager?.isBillingClientReady() == true && billingClientManager?.isFeatureSupported() == true) {
-                            billingClientManager?.purchase(product, customerID, callback)
-                        } else {
-                            callback.onError(CBException(ErrorDetail("Play services not available")))
+                        if (billingClientManager?.isFeatureSupported() == true) {
+                            if (billingClientManager?.isBillingClientReady() == true) {
+                                billingClientManager?.purchase(product, customerID, callback)
+                            } else {
+                                callback.onError(CBException(ErrorDetail(GPErrorCode.BillingClientNotReady.errorMsg)))
+                            }
+                        }else {
+                            callback.onError(CBException(ErrorDetail(GPErrorCode.FeatureNotSupported.errorMsg)))
                         }
                     }
                     is ChargebeeResult.Error ->{
@@ -220,4 +233,13 @@ object CBPurchase {
         return list.toTypedArray()
     }
 
+    fun priceChangeConfirmation(cbProduct: CBProduct, priceChangeCallBack: CBCallback.PriceChangeCallback<String>){
+        try {
+            billingClientManager?.priceChangeConfirmationFlow(cbProduct, priceChangeCallBack)
+        }catch (ex: CBException){
+            Log.i(javaClass.simpleName, "Exception in priceChangeConfirmation ")
+            priceChangeCallBack.onError(ex)
+        }
+    }
+
 }
\ No newline at end of file
diff --git a/chargebee/src/main/java/com/chargebee/android/billingservice/GPErrorCode.kt b/chargebee/src/main/java/com/chargebee/android/billingservice/GPErrorCode.kt
index 4b45854..edcd27a 100644
--- a/chargebee/src/main/java/com/chargebee/android/billingservice/GPErrorCode.kt
+++ b/chargebee/src/main/java/com/chargebee/android/billingservice/GPErrorCode.kt
@@ -1,22 +1,21 @@
 package com.chargebee.android.billingservice
 
 enum class GPErrorCode(val errorMsg: String) {
-    UnknownError("Unknown error"),
-    PlayStoreError("There was an issue with the Play Store service"),
-    BillingUnavailable("The Billing service is unavailable on the device"),
-    PurchasePending("Purchase is pending"),
+
+    BillingUnavailable("The Billing API version is not supported"),
+    PurchasePending("Purchase is in pending state"),
     PurchaseUnspecified("Unspecified state of the purchase"),
     PurchaseInvalid("Failure of purchase"),
     PurchaseReceiptNotFound("Receipt not found"),
-    CanceledPurchase("User pressed back or canceled a dialog for purchase"),
+    CanceledPurchase("User pressed back or canceled a dialog"),
     ProductNotOwned("Failure to consume purchase since item is not owned"),
     ProductAlreadyOwned("Failure to purchase since item is already owned"),
-    FeatureNotSupported("The requested feature is not supported"),
-    ProductUnavailable("Requested product is not available for purchase or its SKU was not found"),
-    ParseResponseFailed("A problem occurred when serializing or deserializing data"),
-    ProductNotFound("Failure to purchase since the Chargebee product was not found"),
-    LaunchError("There was an error on launching Chargebee SDK"),
-    SkuDetailsError("Failure to retrieve SkuDetails for the in-app product ID"),
-    InvalidCredentials("SDK key is invalid or not set"),
-    InvalidClientUid("Client Uid is invalid or not set"),
+    FeatureNotSupported("The requested feature is not supported by Play Store on the current device"),
+    ProductUnavailable("Requested product is not available for purchase"),
+    PlayServiceTimeOut("The request has reached the maximum timeout before Google Play responds"),
+    PlayServiceUnavailable("Network connection is down"),
+    LaunchBillingFlowError("Failed to launch billing flow, try again later"),
+    UnknownError("Fatal error during the API action"),
+    DeveloperError("Invalid arguments provided to the API"),
+    BillingClientNotReady("Play services not available"),
 }
\ No newline at end of file