Contract cancelled but remains open and I keep being debited

Cancelled contract in August, after contract ended yet I'm told its still open and they still debiting me. Went to the mtn store outlet strangely the same stores that open contracts for us cant cancel it, only customer care is able to. I've called over 4times and taken me from pillar to post with no assistance yet i'm still being debited for this contract i cancelled and no one seems to be able to close it each department im taken to just wants to authenticate security questions and assist with nothing they can barely call a manager when you request for one. Spoke to Yanga Mathatha on Thursday 6 Nov 2025 requesting to speak to a manager instead of putting me through to one she kept insisting she wants to ask verification questions that I'd answered with her previous colleague. My money has been debited end of this month October ,over a contract I cancelled in August cause mtn simply enjoys exploiting and making money of their customers ********ly. Taking up a contract with MTN is the worst thing one could ever do.