I recently had the same problem.
I noticed the bug when a paying user pointed out the bug to me.
If it works properly
Item A - Price A - unlock function A
Item B - Price B - unlock function B
Item C - Price C - unlock function C
In case of abnormality
Item A - Price C - unlock function C
Item B - Price B - unlock function B
Item C - Price A - unlock function A
Unintended display and operation will occur in this way.
In-App-Purchases process for the app has not been changed and has always worked fine.
Using the same app version, I checked on an actual iPhone.
The app was displayed normally on iOS 14.8.1, but anomalies occurred on iOS 15.4.1 and iOS 15.5.
I am having a very hard time.
I don't think the problem is on the application side, but I would like to know if there is a solution.
TKHN
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