Similar problem on our app. Paperlist has 30 entries with iOS15, only 5 entries with iOS 15+.
The correct paper matching in iOS 15 is missing in that 5. This makes the printer malfunction.
In addition printInteractionController choosePaper is called several times, always with the same short paperlist. So accumulating is not possible , too.
It would be great to get more ideas what is going wrong here.