Hi everyone. I have a Hotpoint Fridge Freezer FF7190AEX.

Basically, the freezer section isn't cooling so no cold air is going from the freezer to the fridge. The fan is still working. I have had the appliance switched off whilst I went on holiday, in case it needed defrosting. Upon my return, still no change. After an hour or two, the lights flash and it beeps continuously.

There's no visible sign of any ice build-up in the freezer - although I do remember this did build up in the past (when I had a lot of food in the freezer).

What can I check? Replace?