MTN REFUSE TO CANCEL CONTRACTS IN STORE

I only have ****les with data from MTN. No mobile service with MTN. MTN will upgrade and sell new contracts in store. MTN will send messages to the ****le when it knows you will not receive it. It will agree but fail to email monthly statements. It will then harass you on another service providers mobile number from +*** (3 calls silent and 4th call marketing) in one hour. MTN will however REFUSE TO CANCEL OR CONVERT A CONTACT that has expired to a prepaid number in store. Insisting that you have to phone their free number which is only free if you have a MTN phone. The call centre queue in the week between 8 and 4 is notoriously busy. This is the only time you can cancel. Surely this is not right and counter to the consumer protection.