Please share model number of your product to get more suitable answer. Here are some tips that will help you to resolve your issue:
*If the air is blocked at the top or closed off, then the refrigerator will have to run for much longer and the freezer temperature will fall to low levels. Be sure that the vents are not blocked in the refrigerator or the freezer section.
*There are generally two controls knobs in a refrigerator, one is for cold control and that is the thermostat, and the other knob adjusts the air flow between compartments. The air flow should be set to a central location to start. If it is set to one extreme end of the scale, too low or too high, the air exchange may be wrong.If you think that the controls have been reset mistakenly, set them both for a mid range and allow the refrigerator to adjust to the new settings for 24 hours. Avoid excessive opening and closing the refrigerator during that time.