Hi I'm John I will help you with the problem.
You mean you have frost on the freezer panel not the fridge is that correct.
How much frost on the panel
That model has a defrost timer behind the lens in the fridge where the controls are located .remove the lens and look for a hole the size of a dime the part with the small cog in that hole is the defrost timer turn that cog slowly with a flat screwdriver till the fridge shuts off now wait 15 min If the frost starts to thaw replace that defrost timer .
let me know how you make out.