Has this been an issue for ten years? I am still in a rejection loop, can't see the IAP/Sub section in the version. After creating a new sub product, re-building to change the product code the IAP/Sub section appeared, I linked the sub product to the app, added new build submitted for review and the link went away and of course because the product wasn't approved with the binary the in app purchase can't ever work

I am experiencing the same issue, connect reviewers don't seem to even pay any attention to the problems and just reject again and again