Temperature fluctuates in both freezer and refrigerator compartments

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Brand: Frigidaire
Model Number: LGHB2867PF3
Main Symptom: Temperature fluctuates in both refrigerator and freezer compartments
What happens & when: Freezer and refrigerator reach set temperatures overnight but during the day The refrigerator compartment goes as high as 55 degrees. The freezer fluctuates between 0 and 25 degrees. The refrigerator is stuck between two countertops , it won’t budge, I can’t pull it away from the wall, so I can’t check the condenser fan. I can hear a fan running but not sure if it is the condenser or evaporator fan. Also, there is ice buildup on the back wall under the icemaker/water dispenser in the door.

Error Code (if any):
Parts or tests already tried: I’m waiting for more information before I start taking things apart.
Photos / video link:

The ice build-up would in the ice dispenser door would likely be from the door chute not closing properly. This is commonly fixed by replacing the dispenser module. Regarding the temperature in the fresh food and freezer sections, it sounds like the temperatures may be going up after a defrost cycle and the compressor is struggling to get it back down to temperature. If the compressor has been running for an hour, the evaporator cover in the freezer can be removed to check for the frost pattern. If there is not a light frost on the entire evaporator by this time, it would verify the compressor is struggling to get the appliance down to temperature when it is warmer. In a case like this, the refrigerator would need to be pulled out to inspect the condenser coil in the compressor compartment. If it is congested with dust, it will cause the sealed system to struggle to cool things down properly. If this is what is found, cleaning the condenser coil would be the first step.