Utterly bad technical service

Good day, <br> <br> I am on Telkom's 10MB uncapped ADSL line for the last 8 months. I had exceptional good connection till about 6 weeks ago when my sync dropped from 10236kbps to 523kbps. I phoned them 12 times before a technician was sent to me (5weeks) later. The tech (Rudi) confirmed metallic noise on the line that causes the issue. After determining the cause for the low speed, he did NOTHING to resolve problem, the call was closed UNRESOLVED!! Now they are trying to ******** me by telling me I will not be able to get full 10236kbps... I HAVE VIDEO PROOF that my line synced at 10236kbps and I had a download speed of 1,6MBps. Rudi told me they recently changed me to a different connection at the exchange - since they've done that (without my knowledge) my line have been up to ****!! To whom do I forward my letter of retrenchment, as I got fired for **** performance!? It's been 2 weeks AGAIN and I'm STILL WAITING assistance with my line that still sync at 0.5MB. Can you guys Please help me?