Fridge not getting cold, fan tested and working...

The fan won't run if the unit is in a "defrost" cycle. It turns the fan and compressor off so the heater can defrost the coils. If the evap fan isn't running and the compressor isn't running then you may be stuck in a defrost cycle. See if you have a defrost timer that can be manually advanced (looks like a screw head that can only turn clockwise direction). It could be located in the frige section on the roof area. Usually a small hole mixed in with other screw holes that you will have to look up into and see the clock dial screw head. If you find that, manually turn the screw (it will click as notches go by) until you can hear the compressor and fan turn on. If that happens you likely have a bad defrost timer. If you have an "adaptive" defrost unit it will be a small circuit board that controls the defrost cycle and you will have to replace the board.