Telkom USELESS service

Telkom ADSL service is absolutely terrible, i have had their service for a long time and one day it just stopped working, I reported a fault, they sent a technician who came by threatening me to charge for his trip to fix my line (discouraging us to call them for faults), then i don't know what he did - the line was working again, but only for a week, then it went down. This time, it would go down - then as soon as i call, its fixed without anyone coming to my house - but the very next day, its down again - so its up and down intermittent, but down like 80% of the time and Telkom cannot fix it. When i call them they tell me they will charge me for the technician to come to my house to look at my line, which I am paying for, but not working. Why am i paying for a line that DOES NOT WORK - over R800 per month.