ABSA pathetic service

Absa worse service ever. I have been trying to assist my mother in law whom is a pensioner to get her FNB to close her credit card for quite some time now. She has approached ABSA to put a stop to the debit order that FNB keeps deducting but they tell her they can't assist she needs to go to FNB. She is an 83 year old lady and has literally been walking to FNB several times and stand in long queues to get this sorted, however they make promises that the card will be closed, but as soon as her pension is paid into her ABSA account FNB deducts R750 instalments from her account. She doesn't owe them a cent but they keep insisting to deduct this debit order. When it get's returned to ABSA it's R750 less bank charges. The account is still not closed and a few weeks ago they advised her that it will be closed in 5 working days it's now nearly a month already. I sent them an email on behalf of her and 3 weeks ago to reverse the debit order and she is still waiting on her money to be returned. I have advised her to close this ABSA account and open another bank account and transfer her one small policy debit order to this bank, it's the only way FNB cannot attempt to deduct the debit order any longer. Why is it so difficult to close this account she does not want or need. She has requested ABSA to reverse the debit order but to date nothing has been reversed and FNB is still sitting with her money. Please somebody assist to get her money back and bank charges reversed. I cannot see how ABSA cannot put a stop to this debit order.