This Console Error message is due to our inability to retrieve (or find) the plans from AppStore Connect.
This Error can show on iOS 14+ simulators but should not happen when testing on your Device.
It can be due to the fact that you are using the wrong API Key.
If the API Key is correct you can check the following:
Go to AppStore Connect
Check the Paid Apps Contract :
Is it signed?
Has it expired?
Check that the In-App Purchases IDs in AppStore Connect and in the Console are matching
Check that you set a price for the In-App Purchases
Check that the In-App Purchase is available in the country you are testing from
Check that the App Bundle Identifier is correctly set in the console
Check that the In-App Purchase capabilities was associated in X-code