In-App-Purchase Sandbox Receiving UpdatedTransactions with already finished transactions

Hi,
whenever my app launches without being in the background my SKPaymentTransactionObserver always receives multiple already finished transactions in Purchased state from within the last few days.
If I wait for the app to process and finish (by calling finishTransaction) all the transactions, which I verified by the app logs, then kill the app and restart it, I receive the exact same transactions in the updatedTransactions callback again.

This leads to the phenomenon that, when trying to purchase a subscription after app start, but before the old transactions were processed, the app will infinitely wait for the StoreKit dialogs to popup (which never do).

Why do I always receive old and already finished transactions in the purchased state when restarting the app?
Who can guarantee that this does not happen in the production environment as well?

Any help will be appreciated.
In-App-Purchase Sandbox Receiving UpdatedTransactions with already finished transactions
 
 
Q