Frigidaire phsc39eess fluctuating temperature

[mm12]

I have a 2 year old Frigidaire side-by-side counter depth refrigerator. Two months ago, both the refrigeration and freezer section stopped cooling properly.

A Frigidaire service technician replaced the compressor and it started working. However, the temperature in the freezer section started to fluctuate about 10 degrees throughout the day, (i.e. it would be 0 degrees at one time and an hour or two later it would be 8 degrees, then another hour or two later it would be 3 degrees, then it would be back at 0). I called the technician to come back to take a look at it and he said that it was normal for the temperature to fluctuate.

About a month, the refrigerator stopped cooling again.

A second service technician diagnosed the problem as a defective defrost control and defrost bi-metal (?). Both parts were replaced yesterday, but the temperature in the freezer section is still fluctuating. I'm afraid that it will stop working again.

Is it normal for the temperature to fluctuate about 10 degrees throughout the day? Or is there another problem with the refrigerator?

Thank you for any information.

M