We had the same problem but with a sharp tap on the side of the cabinet - the fridge started working again. However, it has happened several times - but usually in hot weather so we moved the fridge-freezer further away from the wall to ensure a good circulation of air, and left a small window open in the kitchen.
This worked for 5 years, but sadly, it has now failed completely. This is the best fridge-freezer we have ever had. Excellent design. We shall miss it. Spares available if anyone needs them.
Liz & Terry, May 2013