They do ours - although I've received an incomprehensible flyer from the conglomerate that now owns our HA, which might indicate they've fired Liberty. I can't tell because the entire flyer is written in meaningless "Working Together For Your Wellbeing" language. I suppose I'll find out when I need a gas safety check - which, come to think of it, is several months overdue!
I think all these maintenance firms just treat large contracts as a money lake. They receive instructions, send out the invoices and don't bother much if they never even attempt to fulfil the instruction.
When an electrician came to look at a fault, which he said wasn't a fault, and went away again after basically calling me stupid, I identified the fault myself and rang the HA to let them know. They sent another electrician to make sure I was right. They were billed for both visits.
I did, however, have a marvellous service visit from Liberty. FIVE engineers turned up! The actual job only took the one bloke 5 minutes, so then they all went down the pub. I imagine the HA paid for 5 man-hours.