Hi,Welcome to Just Answer, My name isXXXXX will be helping you with your appliance issue today.
do you have a make and model #?
actually after looking at the controls you will need to replace the damper control. its like the cold control but closes to stop the air flow to the refrigerator section in yours, its # XXXXX on this diagram. inside the refrigerator section in the back, check and see if the spring came off before ordering this. thanks, Bryan