Billing after termination of contract

Telkom Mobile has to be the most inefficient network I have ever used. My contract ended the end of January, which I sent an email through to cancel the contract as I couldn't go to an actual store. No effort has been made to contact me to let me know the progress all I get is agents who promise to escalate the matter yet its been two months and I am still being billed with no form of communication. I use my time and effort to call Telkom with false hope and promises. The service is **** and I have every reason to sue you. 21 working days have multip****.