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