MTN Extremely Disappointed

I had a contract with MTN from 12/02/2020 to 14/02/2022. The contract had to be terminated because I didn't upgrade. Instead they kept deducting the money from my account without my permission til date. I have gone to the branch where I got my contract on numerous occasions to cancel it but the assistant elaborated that the monthly fee is being allocated to data. The funny thing is this data is being sent to a number that isn't mine because I don't recieve any data on the contract sim cards. I have tried on numerous occasions to stop the debit order on my bank account. I have even gone to the bank branch but they couldn't assist. Upon enquiry with the consultants they said the account will be terminated but til date money is still withdrawn from my account and this extremely unprofessional and infuriating. I will never open an account with MTN or encourage anyone to. Actually I will strong discourage people to not take out contracts with MTN. It's like you're in prison and can't escape this contract.