Note: that this is a US site so getting tech info on a non-US model is difficult.
I did look at the Candy site but could not find any tech info or parts breakdown.

You will have to remove the evaporator coil cover in the freezer and take a look.

Is the evaporator fan running?
Note some units have a door switch that turns it off when the door is opened.
This is required to push the cold air from the freezer into the fresh food section.

Are the evaporator coils heavily iced/frosted up?
This would indicate a defrost problem.
The fan cannot pull air through the coils so cooling is poor.
Shows up first in the fresh food section but will effect the freezer temp as time goes on.
Could be a blown defrost heater, defrost thermostat or a defrost timer.
Most newer unit use Adaptive Defrost (electronic) instead of a mechanical defrost timer.

Is the drain from the freezer compartment to the drip tray under the unit clear?
Could be there is a water/ice build up and this is blocking the cold air from entering the fresh food section.
Very unlikely as usually the symptom is water on the floor of the fresh food section.


Here is a good site with basic refrigerator repair info.
http://www.applianceaid.com/refrigerator.html