App got rejected saying IAP failed (with screenshot from the reviewer attached in the resolution center).
I immediately tested the same build number via testflight and sandbox and it works perfectly fine. Tested three times on different devices and same iOS version (latest 12.1) which they used to test my app too. Also on iPad which they said they used to test it.
Cos this is very rare for me, i had quite a few apps with IAP approved before and never had this problem.
Please tell me how to solve this problem?