Feratel error: ErrorSavingGuestCardData - PersonGroupChangeNotAllowedForPrintedGuestCard

The registration form cannot be saved to the database.
When trying to register a guest via Feratel, we receive the following error “Registration form cannot be saved to the database. ErrorSavingGuestCardData PersonGroupChangeNotAllowedForPrintedGuestCard” What does this error mean?
This error message means that, after the guest card has been printed via the Feratel interface, no further changes can be made.