Telkom is pathetic

The service i have received from telkom is beyond pathetic, i cancelled my adsl line at the end of december, till now they havent cancelled it, they keep charging me and im expected to pay otherwise they cut my phone line, ive called so many times but i can never get through to their customer care, if i do get through by some miracle then all they have to say is they will escalate, i went to the telkom shop to try and speak to them, and still all they can do is escalate the matter. How is this fair? What do i do in a case like this? Carry on paying for something im not using? Really disgusted at the pathetic service.