Why is refrigerator not cooling?

This answer is aimed at the ice maker rather than the whole box as I can’t really tell what is failing from the way the question is stated:

Cause 1

Freezer Temperature is Above 10 Degrees F (-12C)

If the freezer temperature is above 10 degrees Fahrenheit (-12C), the ice maker will not produce ice cubes efficiently. The freezer temperature should be set between 0 and 5 degrees Fahrenheit (-18 to -15C) for the ice maker to work properly. If the freezer temperature is too high, ensure that the condenser coils are clear of debris and the condenser fan is working properly. In addition, check to see if frost has accumulated on the evaporator coils. If the evaporator coils are frosted over, part of the defrost system has likely failed.

Cause 2

Water Inlet Valve

The water inlet valve is an electrically-controlled valve that opens to supply water to the dispenser and ice maker. If the water inlet valve is defective, or if it has insufficient pressure, it won’t allow water to flow through. As a result, the ice maker won’t make ice. The valve requires at least 20 psi to function properly. Make sure that the water pressure to the valve is at least 20 psi. If the water pressure is sufficient, use a multimeter to check for power to the water inlet valve. If the water inlet valve has sufficient pressure and is getting power, but the ice maker won’t fill with water to make ice, replace the water inlet valve.

Cause 3

Ice Maker Assembly

One component of the ice maker assembly might be defective. Since many of the ice maker components are not sold separately, you may need to purchase and replace the entire ice maker assembly. Before replacing the ice maker assembly, check the water inlet valve, water line, and fan. If none of these parts are at fault, and the freezer temperature is at least 15 degrees Fahrenheit, replace the ice maker assembly.