In my app, I need the user to redeem a code outside the app and then capture the transaction in the callback/response from the App Store. How can I test this process? Here's my function for opening a URL: if UIApplication.shared.canOpenURL(url) { UIApplication.shared.open(url, options: [:], completionHandler: nil) } } I am trying to get the transaction object in the TransactionObserver class: // Implementation details... } Here is the link to this class. However, I am not receiving the expected callback in this observer. I am testing on a TestFlight build. My question is: Is it possible to test offer codes in TestFlight? Or is there something wrong with my implementation?