I had exactly the same problem, only after a longer period of storage. I’m told either refrigerant had leaked (no obvious sign if this was what happened), or in some way evaporated. Either way, it stopped being capable of cooling a even a semi filled fridge. The freezer worked fine, which solved the cold beer problem. Couldn’t find anyone who could or would repair it. It was, sadly, new fridge freezer time.
It stood for well over 24 hrs after being moved and was stored upright.