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Hello everyone. I am trying to implement in-app purchase promotion in my app. As the document suggests, I regist an observer to get the SKPorduct user selected in App Store through method- (BOOL)paymentQueue:(SKPaymentQueue *)queue shouldAddStorePayment:(SKPayment *)payment forProduct:(SKProduct *)product;In this method I return a false value and try to show the product information on the subscription page in my project. Things went well on iOS 12 system. However, when I test my code on iOS 11 devices, it crashed due to the priceLocale of the SKProduct was nil. And this was supposed not to appear according to the document. Therefore, I want to know what is happening in this case and is there any way to prevent this crash on iOS 11 system.Below is the error message Xcode showed.error: Execution was interrupted, reason: EXC_BREAKPOINT (code=1, subcode=0x10ce06f04).The process has been returned to the state before expression evaluation.