Storekit1 in Xcode 16, iOS 18.3

I ran into a problem. When using Storekit1 to purchase an SKU, the user payment was successful, but StoreKit1 did return paymentCancelled to my App. I would like to know under what circumstances this problem may occur? How do I fix it? Thank you

Storekit1 in Xcode 16, iOS 18.3
 
 
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