SARS not assisting

My mother updated a new account number to receive her money. As the money had bounced back to SARS as the old account number is no longer active, so they put a ‘Stopper’ for that money to go through again. All documents were sent and they called her to notify all documents were updated. Then she has been calling multiple times to ask them to remove that stopper and the money to come through to her new account, but no assistance and they drop her calls, she was once on hold for over 2 hours with no assistance. ***