Telkom cannot fix ADSL problem

For 3 months now I have intermittent network problems. I have logged numerous calls waiting for 40min at a time for someone to answer the call. Three different technicians have come out to look at the problem. They said it's my router. So at more cost I got another one. Same problem. They said they placed a new line in from the exchange to the house. STILL SAME PROBLEM. Now they say they cannot pick up a problem. I am sitting with virtually no internet for most of the time and they can't fix it. They said its the ISP so they gave me a Telkom test account to run for 24 hours. IT DID THE SAME THING. So it must be the Telkom line. The technicians each time say they going to close the call as it should be fixed. Well, clearly that is just to have good stats from their side because nothing is fixed. I do online tutoring and lost a contract because the line keeps dropping during sessions. YET I HAVE TO PAY MY BILL EVERY MONTH. This is totally unprofessional. I will be cancelling everything and going the wireless way. Never will I use a telkom item or service again. Clearly your technicians need more training.