Mtn ..unauthorized debit

After canceling a contract in April and reversing payments( I did not authorize mtn to debit out my account), sending emails stating that this contract was canceled after it has come to an end,not once was I contacted by an agent to assist with this matter, however many agents call to renew the contract. When I explain that I need assistance with the canceled contract they say they can't assist, give me a number that you have call where you have to wait hours to get through, then get cut off. Mtn your system is not user friendly for the customer, it's only works to assign new contacts. My Account is being debit without my authorization. The old amount was R89 now its changed to R120. There are endless problems with your system. Why would I want to be part of a network that is inconsiderate to its customers.