The TAN is not delivered after entering the access data

Please have the customer check whether a second TAN procedure is still activated in the old bank's online banking. If so, one of them should be deactivated or deleted, as it could cause disruptions.
If the customer has registered more than one device to receive the TAN, it should be checked whether the TAN was not delivered to the other device. If access to one of the devices is no longer possible, it must be deactivated or deleted.