Back button on the "Claim" popup does not work

[sinco-z]

Description:
Steps to reproduce:

1. Open the app and tap the "DROPPING" tab at the bottom.
2. Select any event from the list.
3. On the event details page, tap the "Claim" button at the bottom.
4. A popup appears (see attached screenshot) with a back arrow button at the top left.
5. Tap the back arrow button.

Expected result:
Tapping the back arrow should close the popup and return the user to the previous screen.

Actual result:
The back arrow button does not respond and the popup remains open.

Suggestion:
Please fix the back arrow button so that it properly closes the popup and returns the user to the previous screen.

Screenshot: