I am facing an issue with my app. It works perfectly on TestFlight, and I have tested it on several devices, where it also runs without any problems. However, when the app is tested in the Apple testing facility, it shows an unexpected server error message. I have tested the app using multiple VPNs and different locations in Sri Lanka, and it works perfectly in all cases. It also works correctly when distributed through third-party app stores. At this point, I am not sure what is causing this issue. I have already submitted more than 10 app versions, each with different fixes that I thought might solve the problem, but the issue still persists. Could someone please help me understand what might be causing this problem? (the above provided screenshot from apple)