Not cooling or freezing

Brand: kenmore
Model Number: 363.58272892
Main Symptom: not cooling or freezing
What happens & when: fridge starting getting warm staying about 45 to 54 degrees fahrenheit. Freezing was freezing changed defrost heater now fridge is same and freezer is 40 to 45 degrees inside fan was running constantly now stopped

Error Code (if any):
Parts or tests already tried: defrost heater assembly
Photos / video link: