Irritating attitudes and lack of delivery

My mother went on pension in January and we requested a change in banking details for the debits. We went to the Pretoria branch and submitted documents there. 3 months down the line still no change has been done and when i call they tell me they haven't received the documents yet the Pretoria branch says they've sent them. Been on the phone for over an hour and passed from department to department, person to person and still the issue not resolved. You managed to change the banking details for refund (what for i don't know) but not for debit, why? Who is *********** and not doing their job? Useless company at its best.