New ADSL installation still not working

I had an ADSL line installed at my premises on the 1st of April 2016. I had received my login details from Telkom and proceeded to setup my router. I have done this many times in the past so I know what I am doing. The DSL light on the router came on but there was no internet light. <br> I phoned support and they helped me go through all of the settings and it still didn't work. They advised me to take the router back to the store I bought it from as they suggested it was faulty. That was not the case.<br> I eventually got someone on their side to report the line as faulty. I called them to check the progress on the fault and they admitted to me the fault was on their cabling on their exchange. A week later they sent a technician to my premises. He said he checked the line and all was working. They then closed the call and said it was resolved. <br> I still wasn't able to go on the internet. I logged another call and they haven't come back to me.<br> I then received an invoice on the 12th of April for over R2000.<br> The invoice doesn't make any sense and I refuse to pay for something that is not working.<br> I have been on the phone with them almost daily with no joy or any resolution in sight.