Adsl and line faulty

I have a recurring issue with my line that's not being resolved. The quality of the line is shocking and noisy. I've lodged complaints in the past and it has been fixed but after 2 or 3 months it happens again so it's clear that the root cause is not being fixed. I've lodged a fault over 2 weeks ago and it's even been escalated for at least a week and a technician still hasn't come through to investigate. Every time this happens I am stuck without internet for 2 to 3 weeks.