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Parts for Whirlpool GX5SHDXVB01 Refrigerator - AppliancePartsPros.com

Cannot tell much from the info you were given.

Where is the frost in the freezer?

It could be that the frost is getting on/into the evaporator fan and causing problems.

The below assumes the frost is on the freezer walls and food.

I would check the freezer door seals.
Take a 2 inch wide piece of paper.
Place it between the seal and the frame and then pull it out to see if the seal is OK.
Work your way around the door.

Another possibility is that the defrost thermostat is not opening when it should.
The defrost cycle is a fixed time event, usually around 30 minutes.
But lets say that the frost is melted off the evaporator coils in 15 minutes, then the defrost thermostat opens and kills power to the defrost heater.
This prevents excessive heating up of the freezer compartment.
For some reason I cannot see it listed in the parts but it will be clipped to the top of the evaporator coils. it may be part of the heater or the freezer wiring harness.

yetr another possibility is that the freezr temperature is not being regulated properly and it is sometimes getting too warm.
You would have to check and monitor the freezer teperature with a thermometer.
it should be between 0 and 5 degrees F.
During defrost it may go higher but should not get above freezing.