Non ending loan payments

Since my mom made a loan the early 2000's. She paid up her account but absa keeps making debit order transactions even after they had resolved the issue and paid back approximately 3600 for over payment in 2016... This problem keep persisting... Everytime we reverse the debit order we lose almost forty rand every month. We need help in this matter. We can't keep paying up a loan that was cleared years ago... I fail to understand how can they still be taking our money almost a decade after the initial loan was made!