Contract not being cancelled.

I have a data contract with Telkom Mobile on a month to month basis. I have been trying to cancel my contract since 12 August but Telkom Mobile refuses to cancel my contract or give me feedback. They keep saying I signed a new contract which I never did and they cannot provide proof neither are they cancelling my contract. After numerous phone calls I keep getting the same feedback that someone will call me but no one does. I am now paying for a contract that I don't want.<br> <br> Ismail