I have a Samsung RF28HFEDTWW french door fridge. We've had it about 2 years and I use the lower ice to fill my mug for work every day.The lower ice maker has quit working. The upper unit and water in the door still works fine. I have tried to reset the lower unit and can hear the tray motor operating but still get no ice from the unit. I have tried to research the issue but find very little info on this model. I need help on where to start the troubleshooting on this thing. Ive replaced ice makers and water pumps in the past,and troubleshot/repaired a couple rv units in the past so complexity really isn't an issue. Any help on where to start would be greatly appreciated.