Hey, LR_FR! I had the same problem. The problem disappeared after I stopped checking the receipt on the first launch of the application has the receipt sandbox. Here is the code:
if appLaunchConfiguration == .firstLaunch && Bundle.main.appStoreReceiptURL?.lastPathComponent != "sandboxReceipt" { PurchasesManager.shared.restorePurchases(receiptRefresh: .noRefresh) }