App rejected for - Guideline 2.1 - Performance - App Completeness

Hello,
My app got rejected for the following reason:

Guideline 2.1 - Performance - App Completeness


We found that your in-app purchase products exhibited one or more bugs when reviewed on iPad running iOS 14.3 on Wi-Fi.

Specifically, we were unable to complete IAP transaction.

Next Steps

When validating receipts on your server, your server needs to be able to handle a production-signed app getting its receipts from Apple’s test environment. The recommended approach is for your production server to always validate receipts against the production App Store first. If validation fails with the error code "Sandbox receipt used in production," you should validate against the test environment instead.


When I test the purchase on test flights it works just fine so I don't understand what should I do if on my end it works but the apple review saying it doesn't on their side?
I've had exactly the same response after submitting an update to my app, did you find out any further information? My app seems to be fine when I test...?
No luck yet,
I get a rejection on every binary I am sending to review for that reason, even though it works on all of the devices I tested it on.
I think it is an issue with the apple review environment but I don't really know what to do next because they keep rejecting the app for no reason.

Is anyone else having this issue?
Can any Apple representative help us with this issue?
Hi all,
i'm facing the same issue. Some suggestions?

Thanks

Hey guys. How are you? 2024 continuing with the same review problems.

I'm trying to find a solution, but I keep receiving the same message without much explanation of what needs to be done.

App rejected for - Guideline 2.1 - Performance - App Completeness
 
 
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