Telkom refusal to cancel service

I have been trying to cancel my landline since Feb 2018. I am still trying to cancel it. After getting a reference number from them on Hello Peter, they still have done nothing. I went into the store at the Glen and a lady assured me they would call me by the next Tuesday. Nothing. No phone call. I am still getting billed. I will not be paying this outstanding amount because it is ******** what Telkom is doing.