Impossible to cancel Telkom Mobile contract

In February 2015 I received a message from Telkom Mobile that my contract was due for an upgrade. I have decided to cancel the contract instead and went to the Rosbank Mall Telkom branch where I completed a cancellation form The consultant mentioned that it can take up to 21 days for the cancellation to occur. After 21 days I have contacted Telkom Mobile. The consultant on the helpline logged the call and mentioned that a consultant from the customer service department will call me. It never occurred. I have called the call centre numerous times over the past few months and every time I get the same story: the cancellation department will call me to confirm cancellation. On Wednesday 13 January 2016 I visited the Cresta Telkom branch. The consultant mentioned he could see that I have tried since February to cancel the contract. He logged a request and mentioned I will get a call from the cancellation department within 24hrs. This has not occurred. How can I get hold of someone in the cancellation department to cancel my contract seeing that logging requests do not work. I am frustrated HELP!!!!