At the bottom rear is the compressor, a black pot shaped item.
Is this running?
If it is, is it very hot?
Yes it is running, and yes it is very hot.
Thanks for that.
Not good news I'm afraid.
The compressor being hot is normally a restriction in the foamed in pipework.
The refrigerant isn't being pumped around the system so there's little, or no, cooling taking place.
It's not a diy repair and there is a chance that it cannot be repaired.
You need a refrigeration engineer to attach pumps and gauges to the compressor pipework to determine if it's blocked/restricted or, if it has a leak.
(no refrigerant can give similar fault).
Sorry, I wish there was an easy, inexpensive fix.
If it can be repaired, the bill could be over £200 for a compressor and regas, or as little as £80 for a regas (all depends on your engineers labour rate).
You could try Hotpoint to see if they have a fixed price repair plan for it.
They normally start around £120 and give different guarantees.
Check it out, see what you find and get back to me if you need more help.
Hope this helps