If its making a lot of noise than that's probably the fan in the freezer catching on ice that is building up.
This happens for 2 reasons,
1 - The most common, the freezer or fridge door has been left open slightly (it only needs the smallest of gaps left overnight to cause it. Usually caused by food pushing on the door when loaded with lots of food or stacked forward. Resolution: Turn off and unplug the unit for 2 full days to defrost the whole unit - it can take this long unfortunately. You will need to put towels on the floor to catch potentially quite a bit of water.
2 - An issue with the auto defrost system, like a failed heater, although this is super rare. Would need an engineer to identify and resolve.
Of course it could be other things, but based on defrosting food and noise this is my educated guess.
