Poor service

Hey, I've been a virgin customer for only 6 weeks now and I am not impressed. I had issues with installation where the 1st engineer installed the wrong equipment for broadband and telly,  realised it was the wrong equipment drilled holes and attached cables then removed them lifting chunks of plaster off of the walls. It took 3 different engineers(on different occasions)to get us up and running with our package. Only a week later it stopped working had to get another engineer out and today it is off again needing another engineer visit tomorrow.

I submitted a complaint after all the problems with installation and 4 weeks later haven't heard anything back. I spoke to someone over web chat about the complaint and that I had not heard anything and 3hrs 30 mins later after pleading to speak to their manager all they could offer was £50 credit on my account which I declined and I'm  now waiting on a deadlock letter being posted out that could take up to 28 days to arrive. 

I was with sky for 20+ years and never had any issues like this. I really don't know what to think. Any suggestions??