MTN Month to Month Cancelation Ignored and keep on debiting

MTN is pathetic and streching the cancelation process to get more money even though I canceled my contract 4 times. I had a LTE modem contract with MTN for 2 years and my contract term ended on November 2023, I since then went on a month to month basis with MTN till February 2024 when I canceled my contract with them since then they keep on debiting from my account and sending me sms'e that their taking action on my credit rating when I Stop the debit order from my banking app, the first cancelation was made Februarie with Ref number REF *** and then again in March with REF *** and insisted on a confirmation of cancelation via email, that never happed and then recieved sms'e again in april and canceled my contract at our nearest MTN store in Vanderbijlpark and Gavin assisted us with REF 1-,*** which wasnt very helpfull because they just captured a cancelation all over, but can't give any feedback on previous refrence numbers all cancelations are on their system but never accepted, I insist on a refund from first cancelation period, we installed fibre that is 10x faster for the same amount and now we have pay for fibre and MTN because MTN cant cancel the month to month basis.