Roofing "Fix" Nightmare

Pathetic all round! Long story short... A few years ago a hail storm wrecked my roof, they came and redid the entire thing. They said it was good to go for another 8-10 years without having to do anything. Few years later another storm hits again, and this time they wont fix it, cos they said it was due to negligence. The "negligence" comes in saying that it wasn't waterproofed and that tiles were lifting allowing water to get in. The lifting tiles and water getting in was due to them not doing the job properly in the first place. When they "fixed" the roof, the didnt install it correctly according to product installation specs, they didnt seal it at all, and they even left some of the old damaged roof tiles behind instead of using brand new ones throughout, so yeah obviously there was negligence, except it was from their side. It's been over a year now since i've started this complaint with no luck or assistance from them. They are chilled with taking my money every month but don't give a **** about actually fixing their ***** up in the first place. DON'T USE THEM FOR ANYTHING! Ombudsman is next on my list cos they're just as useless.