No service, no feedback and paying for it.

This is my 2nd complaint on the exact same problem. I took a telkom mobile uncapped data contract after the sales agent confirmed they would upgrade my old contract to the new contract, months later the old contract is still not cancelled and I am still paying for it, i have made numerous calls to telkom only to be told I can only be assisted by their cancellation department which i cannot contact and am told they will contact me, I have not received any callemail a month later.