My refrigerator will not cool below 50 degrees

Brand: Kenmore
Model Number:253.54669400
Main Symptom: Refrigerator too warm
What happens & when: Fridge won’t cool below 50 degrees. Freezer is also on the warmer side at around 15 degrees. The evaporator fan pulses instead of staying on. Can feel air go through the vent at the top of the fridge when it does pulse (this is a side by side). Freezer does have ice build up on the back, but when I replaced the fan I cleaned all of that off including the coils and it still never went below these temperatures even before the ice built back up.

Error Code (if any):
Parts or tests already tried: Replaced evaporator fan
Photos / video link: