telkom delaying cellphone contract cancellation

I have a cellphone contract with Telkom, the contract period has expired but they are still billing me on the contract even though I followed procedure and went to the waterfront store in November to cancel it, a few days later was told that I went early I must come back in December and I did. Seemingly they did not process the cancellation. I was also told by the call centre staff that there is no cancellation case on the system and that I must go back to the store and ask for the forms I filled in and that I will start over.<br> <br> I want them to cancel the contract immediately and take their data and airtime back, I am not gonna use it. They must change my line to prepaid immediately because I do not want the contract to continue and I followed procedure.