diff --git a/include/tgbot/types/CallbackQuery.h b/include/tgbot/types/CallbackQuery.h
index 58e02b35..6d994f42 100644
--- a/include/tgbot/types/CallbackQuery.h
+++ b/include/tgbot/types/CallbackQuery.h
@@ -5,6 +5,7 @@
 #include "tgbot/types/Message.h"
 
 #include <memory>
+#include <optional>
 #include <string>
 
 namespace TgBot {
@@ -35,7 +36,7 @@ class CallbackQuery {
     /**
      * @brief Optional. Identifier of the message sent via the bot in inline mode, that originated the query.
      */
-    std::string inlineMessageId;
+    std::optional<std::string> inlineMessageId;
 
     /**
      * @brief Global identifier, uniquely corresponding to the chat to which the message with the callback button was sent. Useful for high scores in games.
diff --git a/include/tgbot/types/InputInvoiceMessageContent.h b/include/tgbot/types/InputInvoiceMessageContent.h
index 17721c87..aba5ab13 100644
--- a/include/tgbot/types/InputInvoiceMessageContent.h
+++ b/include/tgbot/types/InputInvoiceMessageContent.h
@@ -71,7 +71,7 @@ class InputInvoiceMessageContent : public InputMessageContent {
      * At most 4 suggested tip amounts can be specified.
      * The suggested tip amounts must be positive, passed in a strictly increased order and must not exceed maxTipAmount.
      */
-    std::vector<std::int32_t> suggestedTipAmounts;
+    std::optional<std::vector<std::int32_t>> suggestedTipAmounts;
 
     /**
      * @brief Optional. A JSON-serialized object for data about the invoice, which will be shared with the payment provider.
diff --git a/include/tgbot/types/InputSticker.h b/include/tgbot/types/InputSticker.h
index a5b5a313..6987dd01 100644
--- a/include/tgbot/types/InputSticker.h
+++ b/include/tgbot/types/InputSticker.h
@@ -4,6 +4,7 @@
 #include "tgbot/types/MaskPosition.h"
 
 #include <memory>
+#include <optional>
 #include <string>
 #include <vector>
 
@@ -50,7 +51,7 @@ class InputSticker {
      *
      * For “regular” and “custom_emoji” stickers only.
      */
-    std::vector<std::string> keywords;
+    std::optional<std::vector<std::string>> keywords;
 };
 }
 
diff --git a/include/tgbot/types/Message.h b/include/tgbot/types/Message.h
index 66f29561..01a6196c 100644
--- a/include/tgbot/types/Message.h
+++ b/include/tgbot/types/Message.h
@@ -254,7 +254,7 @@ class Message {
     /**
      * @brief Optional. Caption for the animation, audio, document, photo, video or voice
      */
-    std::string caption;
+    std::optional<std::string> caption;
 
     /**
      * @brief Optional. For messages with a caption, special entities like usernames, URLs, bot commands, etc. that appear in the caption
diff --git a/include/tgbot/types/WebhookInfo.h b/include/tgbot/types/WebhookInfo.h
index a55ed088..7e475eb8 100644
--- a/include/tgbot/types/WebhookInfo.h
+++ b/include/tgbot/types/WebhookInfo.h
@@ -61,7 +61,7 @@ class WebhookInfo {
     /**
      * @brief Optional. A list of update types the bot is subscribed to. Defaults to all update types except chatMember
      */
-    std::vector<std::string> allowedUpdates;
+    std::optional<std::vector<std::string>> allowedUpdates;
 };
 }
 
diff --git a/src/TgTypeParser.cpp b/src/TgTypeParser.cpp
index e6039c87..6fbf8040 100644
--- a/src/TgTypeParser.cpp
+++ b/src/TgTypeParser.cpp
@@ -375,8 +375,10 @@ DECLARE_PARSER_FROM_JSON(WebhookInfo) {
     parse(data, "last_synchronization_error_date",
           &result->lastSynchronizationErrorDate);
     parse(data, "max_connections", &result->maxConnections);
-    result->allowedUpdates =
-        parsePrimitiveArray<std::string>(data, "allowed_updates");
+    if (data.contains("allowed_updates") && !data["allowed_updates"].is_null()) {
+        result->allowedUpdates =
+            parsePrimitiveArray<std::string>(data, "allowed_updates");
+    }
     return result;
 }
 
@@ -393,7 +395,7 @@ DECLARE_PARSER_TO_JSON(WebhookInfo) {
                  object->lastSynchronizationErrorDate);
         json.put("max_connections", object->maxConnections);
 
-        json.put("allowed_updates", put(object->allowedUpdates));
+        json.put("allowed_updates", object->allowedUpdates);
     }
     return json;
 }
@@ -3489,7 +3491,9 @@ DECLARE_PARSER_FROM_JSON(InputSticker) {
     parse(data, "format", &result->format);
     result->emojiList = parsePrimitiveArray<std::string>(data, "emoji_list");
     result->maskPosition = parse<MaskPosition>(data, "mask_position");
-    result->keywords = parsePrimitiveArray<std::string>(data, "keywords");
+    if (data.contains("keywords") && !data["keywords"].is_null()) {
+        result->keywords = parsePrimitiveArray<std::string>(data, "keywords");
+    }
     return result;
 }
 
@@ -3503,7 +3507,7 @@ DECLARE_PARSER_TO_JSON(InputSticker) {
     ptree.put("format", object->format);
     ptree.put("emoji_list", put(object->emojiList));
     ptree.put("mask_position", put(object->maskPosition));
-    ptree.put("keywords", put(object->keywords));
+    ptree.put("keywords", object->keywords);
 
     return ptree;
 }
@@ -4343,8 +4347,10 @@ DECLARE_PARSER_FROM_JSON(InputInvoiceMessageContent) {
     parse(data, "currency", &result->currency);
     result->prices = parseArray<LabeledPrice>(data, "prices");
     parse(data, "max_tip_amount", &result->maxTipAmount);
-    result->suggestedTipAmounts =
-        parsePrimitiveArray<std::int32_t>(data, "suggested_tip_amounts");
+    if (data.contains("suggested_tip_amounts") && !data["suggested_tip_amounts"].is_null()) {
+        result->suggestedTipAmounts =
+            parsePrimitiveArray<std::int32_t>(data, "suggested_tip_amounts");
+    }
     parse(data, "provider_data", &result->providerData);
     parse(data, "photo_url", &result->photoUrl);
     parse(data, "photo_size", &result->photoSize);
@@ -4373,7 +4379,7 @@ DECLARE_PARSER_TO_JSON(InputInvoiceMessageContent) {
     ptree.put("currency", object->currency);
     ptree.put("prices", put(object->prices));
     ptree.put("max_tip_amount", object->maxTipAmount);
-    ptree.put("suggested_tip_amounts", put(object->suggestedTipAmounts));
+    ptree.put("suggested_tip_amounts", object->suggestedTipAmounts);
     ptree.put("provider_data", object->providerData);
     ptree.put("photo_url", object->photoUrl);
     ptree.put("photo_size", object->photoSize);