Technicians don't even know simple networking terms

My 20mbps ADSL line was having high packet loss and high latency after the recent rains. I called for assistance, and the call centre did port resets and port interrogations and quality something somethings - but none of it helped, so eventually they logged a fault. The technician said my router was overheating and I should get a dlink and increase my line speed (I really don't need more than 20mbps) - So I purchased a new router and called sales to have the speed increased, they told me 20mbps is the fastest I can have on ADSL and fibre isn't available in my area. With the new router installed I still had the same problem, so I called for help again, and they did all the port interrogations and resets as usual, but the problem stayed, so they logged a new fault. Today the technician called me and said that because I hadn't increased the line speed there wasn't anything he could do, I need to increase the speed of the line because I had a TV. So I explained that the problem wasn't the TV, it wasn't speed, even if I removed the TV, there was still HIGH PACKET LOSS and HIGH LATENCY - he said there were other things on the network that can affect it and I need to upgrade my line speed. I called the call centre again to ask about increasing the speed. Again they said I couldn't increase it as I was on the maximum. Then I called again and twice got disconnected while trying to explain the problem . So I called a 4th time today and was told that all she could do was "interrogate the ports" but I needed to be on-site to reset the router - so she couldn't help me as I was at work. I am absolutely gobsmacked at the useless so-called assistance that you have provided. I am paying for my line and for my internet subscription and I am unable to use them because your technicians don't even know what packet loss or latency is or how fast the lines in the area are. I am angered that the fault was cleared TWICE without being resolved and that the technical guys don't even seem remotely interested in testing the line or diagnosing the problem and I have to call back again and again and again to try fond someone who can help me, all the time I sit paying for services I am unable to use. Absolutely pathetic service.