I have an Indesit CA 55 Fridge freezer, that has stopped cooling. The noise it makes seems fairly regular and I cant see anything wrong with the underside or round the back where the compressor is. All seals seem fine too. I’ve had it for about 4 years with no previous problems.
If it sounds like it’s running and it’s not cooling then most probably it’s a refrigerant system issue. If so, you will not see any visual sign of that.