Whirlpool Freezer WSF26C3EXF01 does not cool (which means fridge either) when set to recommended 0 degrees but works at -1 -2 -3 -4 -5

Please make sure to click on General above and select the correct appliance type first.

Brand:whirlpool
Model Number:WSF26C3EXF01
Main Symptom:does not cool (which means fridge either) when set to recommended 0 degrees but works at -1 -2 -3 -4 -5
What happens & when:

All test pass in diagnostics

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

It would be recommended to check the thermistor to make sure that it is good. If this is good then it sounds likely that there may be an issue with the main control board.

The thermistor passes the diag.

Could thermistor not work only on certain temperature settings? I would think it would fail anytime? Your thoughts?

It is a possibility but that is why you would want to test it. If it is good then the control board would be the likely issue.