App store rejecting my app cause Chat is loading

I created the app with React native. The login flow was made to init the cometchat with the corresponding id value after logging in through firebase. As a result of testing the app through emulator, real device, and TestFlight, the chatting worked well. However, when i upload it to the app store connection, the tester said ‘still loading indefinitely when we tapped on the “Chat”’. I cannot figure out why this happen.
Do you have any suggestion? About Why Chatting correctly on my devices and not working on apple appstore tester.

I was also denied posting it on the online store in the past.

I have uploaded my created application to ModSuper. I contacted this reputable supplier.