Said garage has received my letter of complaint and both the branch and head office contacted me on Friday when I was at work - they left a message to call them back. Really not sure I can be bothered with doing so. I was booked in today to get the lock looked at but I didn't bother turning up.
These garages are approved by a break down service so I've also sent on a copy of my complaint to them.
I would have went along at least it would give them an opportunity to rectify any mistakes they have made and further inspect the vehicle