MTN Contract Cancellation Nightmare

I went through the extremely tedious process between July and August 2021 to cancel a contract that was incorrectly sold to me telephonically. I specifically asked that a new contract be linked to my existing number. That didn't happen and MTN apparently couldn't link at afterwards. Thus I was forced to pay cancellation fees to cancel, the useless contract, which I did in August 2021. I received confirmation via email as well as a reference number.

But then I am still getting billed every month, and since then I have been trying to resolve the cancellation. I have received another ref number even, but these numbers are seemingly useless, as nobody can assist me. Now I am being sent letters that states I will be blacklisted because I am not paying the contract.

There is no living person that I can talk to that can assist. Nobody in the shops can help, and no one on the phone , if I ever get through to someone, can ever help.

I am at a point where I really do not know what else to do. I do not have more money to give MTN, which is also morally not right.

I am writing this to try another avenue to get through to MTN for assistance.