Why is my Mistral Model FF72/FF92 Fridge/Freezer lukewarm and not freezing?

The fridge compartment is cool but not cold and the freezer isn't freezing anything and can't be used either to be fair.

I would like to repair it but need to understand where the problem is and what part(s) may need replacing.
There is a flashing temperature sign in the display panel above the fridge door but there isn't any solution in the instruction book that is useful.

Can anybody assist please?
Thanks

Hugh, October 2012