fridgefreezing up

I hope someone can help!!! I have a Hoover frost free fridge freezer (don't know model number). The fridge has started to freeze up and is ruining all the food, the freezer is working fine. I turned of the whole appliance for 24 hours checked their was no blockage from the hole in the fridge and through the tube at the back. After turning it back on the fridge just started freezing up again. Does anyone have any other ideas of what I could do to fix this problem.

Hi Lorjam, There will be a damper in the fridge section where cold air from the freezer enters. This could be mechanical but most likely electronically controlled. have to know if you have a side/side or freezer top/ freezer bottom fridge.