Cancellation of a Contract that lapsed

MTN doesnt want to cancel my contract. I had a data contract which ended on the 17/09/2021. I requested that they cancel the contract and migrate the line to prepaid. I even received an sms that informed me that the contract has ended and moves to a month to month contract which I rejected. For some reason all the agents I speak to in the cancellation department inform me that the cancellation is going to be processed but if I check on the app profile nothing has been done. Infact MTN is still billing me. Lerato in the cancellation department made false promises that this would be resovled but nothing is being done. Here are a list of all the references I have received from MTN and nothing is done ***, ***, ***, 1-***, ***, ***, ***, 1-***. On each call I make to this cancellation department, it takes an average of 45mins before an agent picks the call. If anyone knows laywers who can handle my situation the way MTN should understand please help. I am tired of wasting my precious time this these agents at MTN.