I have a Russell Hobbs undercounter fridge freezer, brand new as of last week. I have thermometers in both the fridge and the freezer sections, the fridge appears to be fine as the temperatures don't rise above 5c, it generally fluctuates between 1c and 4c.

As for the freezer, it seems to get down to temperature fine (min -25c) but it doesn't seem to maintain the temperature well. It's currently about half full and rises to around -15c before the compressors starts up again to cool it down (goes down to about -22c at the moment).

I've called Russell Hobbs and they suggested unplugging it and leaving it for 24 hours before plugging it back in. I bought it to replace an older fridge freezer that was doing the same thing (although worse). I'm not sure if there's something about the environment it's in that may be causing it. It's sat on carpet (thin carpet but still) in a small space underneath the kitchen worktop (can't do anything about this unfortunately), could this be an issue?