Telkom wrongly billing and now blacklisting me

I am being billed for a service that does not exist and that I have not asked for. I have queried this so many times with Telkom. I have numerous reference numbers yet it has not been resolved 7 months later and no-one ever comes back to me, follows up or makes any attempt to fix the error. I have requested that they provide proof that I did indeed asked for the service. I have asked for telephone recordings as proof which they fail to provide. Today I was called by a legal representative and have recieved a blacklisting notice. Telkom is at fault yet I have to struggle to solve the problem. Now my name is being blacklisted. Totally unacceptable.

Backstory: I moved back to Gauteng from CPT last year and moved back in with my parents temporarily. In December the ADSL at my parents house was very very slow and I called Telkom. The lady over the phone insisted that there is not internet at that address or that line. I told her I was literallly on the interner while speaking to her but it was very slow. After a very difficult conversation she said she will sort it out. Her interpretation of this was apparently that I had ordered a new line. Which I certainly did not and have challenged them to prove that I every asked for it. Since then I have been billed every month for a line that doesn't exist and that I did not ask for. On top of that my parents are being double billed for a DSL faster bundle which again no-one asked for.

We have been at Telkom stores and sent many mails but all I get is an ongoing bill (which is now already in the thousands) and now a legal threat. I feel very frustrated and don't know what else to do to resolve this. Telkom does not seem interested to help at all.