Service "Champions" Unable to action cancellation of a contract

MTN Service Champions are no champions. Late late year I requested cancellation of an account, as well as to block to the sim since the device was ******. To date they have still not actioned the cancellation and I am still paying for this account. The "service champions" are unable to assist and I am transferred from pillar to post. At the same time, I am receiving SMS's stating that should this number not be upgraded soon my account will continue on a month to month basis, but the amount debited to my account will be increased. I am not given any reason as to why the contract is not cancelled or what the problem is. My account is up to date and the contract on this particular number has run full term.