Telkom account query

I have a problem with my account. I was billed incorrectly, my service is suspended and nobody help to solve the problem. Last year I had exactly the same problem. I have done with Telkom now. I cancelled my service with them and are going to take matters further. A lady in Bloemfontein did her best to connect me with the right person. That supervisor called me and said a Cindy will call me. It is 3 weeks later. I called them weekly, with no reaction from their side.

What am I to do now?