I've replaced the electronic control board, the defrost thermostat and the heater has continuity but after 4 or 5 days the freezer is still freezing up solid. All door seals are also like new and the fridge works great until it freezes up. Any ideas on what I should do next? Any help will be greatly appreciated.

The radiator looking part in the back of the freezer is covered in thick, packed, snow like ice. I always know its frozen when I hear the compressor kicking on and off rapidly...sounding like its struggling to pump coolant through the iced up coils. I then remove the inside back panel of the freezer and let it sit unplugged with the door open for hours....sometimes days depending on what's in it. Usually just beverages because it is not my only fridge.

Everything checks out. That's why I'm so confused. I just installed a brand new board and thermostat. I figured that would fix my issue but sadly, not yet. I'll investigate further and report any new findings. Thank u.