MTN Contract

I have an contract with MTN, the contract was supposed to expire in August 2023 but still I'm paying a service fee for a contract I can't utilize or close.

November to December 2022 my contract was in arrears, they proposed an early settlement. I settlement the account with R21 000. After settlement I was surprised to get a monthly bill. They say they had to continue with the service charge of the plan till endo of the contract, which was in August 2023. I then asked them to give me a simcard/ simswap so that I can utilize the service plan. Into my surprised they can't do the simswap because the number is not on my name anymore but I'm expected to pay. I stopped paying it, End of August I asked for contract termination, they said the account will remain active until I settle the latest balance. This is so ubsurd because MTN is unable to help me use the service and they also can't help me with termination. No they handing me over to the lawyers for the remaining R4000.