ABSA : exceptional service my foot!!!

I can believe that ABSA has a rating between 2.5 and 3.4. I do, however, have to say that the Bank Manager and Staff at ABSA Franschhoek is MOST helpful and efficient. It is their Head Office who leaves them in the lurch. I had a personal loan with ABSA and paid it off in full earlier than needed in December 2018. All of a sudden for the last 4 months I receive a sms again to say please fund your account sufficiently so that the debit order for your Personal Loan can be deducted and every month they deduct just short of R900 again for my Personal Loan!!!! When I go into my online banking, it shows that I do not have a Personal Loan anymore and owe NOTHING!!! I have written numerous mails and phoned and have been sent from pillar to post regarding this matter, Each time I am referred from one Department to another, I receive a mail to say "Your case has been resolved and the file has now been closed. Please rate the service you received from us."!!!!!!!!! NOTHING has been resolved. Nobody has given me an answer. At branch level they are not allowed to help and refer me to the Head Office....who does NOTHING!!!!! What am I to do????????? I have been a client of ABSA for the past 52 years.....a superb way of ABSA to show their loyalty and thanks to half-a-century-clients by giving us service like this...