Our freezer is working great, but we had to make one small change.
Our freezer compartment is aft of the refridgerator compartment. An insulated wall seperates the two. Holes in the wall allow cold air from the freezer compartment to flow through the refer side, and the balance was based on luck. Sometimes food would shift around, change the airflow, and the freezer would thaw or the refer would freeze.
We used a flexible cutting board to create an air dam inside the freezer compartment. Using the whole “cold air is heavier” section of the physics book, we can now count on everything below the top of the air dam, and everywhere inside the freezer evaporator, to be super-duper cold.