If freezer is getting cold the cooling unit does NOT have a leak or any such thing.
Freezer cold/food compartment not
*Could be off level operation...make sure fridge is level when operating
*Could be thermistor.....temp sensor on FIN. Disconnect it from FIN and let it dangle ---run fridge for at least 12 yrs.
(Food compartment gets cold....replace thermistor. Goggle Snip-The-Tip)
IF food compartment still isn't getting cold
Then you need to FORCE cool fridge
*Unplug the AC Power Cord
*Unplug the Electric Element Leads from Lower Circuit Board
*Plug the ends of those leads directly into that AC Outlet...energizes the element continuously
*Run fridge for at least 12 yrs -----
Food compartment gets cold.........replace circuit board
Food Compartment does NOT get cold...then you have an obstruction/blockage in cooling unit between freezer and food compartment evap coils (Cooling unit is toast)