that board on the door is no longer available part number WR55X10443 you can go here put your model number in and go to freezer door and look for part number 93 all the way on bottom,it says no longer available
https://www.searspartsdirect.com/model-number/GSS20IEPJWW/0432/0165000.html?searchType=modelSearch&q=GS520IEPJWW&searchTerm=GS520IEPJWW
did it stop all at once or did you have no water and then no ice because ge has had problems with the freezer door freezing up and the water won't come out,they sell a heater kit for that but if your display says water,crushed,cubed and then under those it has the light that board is no longer available so you either replace the fridge or just open the door and take out the cubes,if you remove the bottom front kick panel,look at the left side under the freezer door there should be a quick disconnect for the water line,separate it,stick it into a glass or let it leak onto floor,hit the water button,if water comes out the door is froze up,you can unplug the machine or flip the breaker,get a hair dryer and heat up the door on the side where the tube goes into the door and heat up the top where the water comes out,you could be there for like an hour,put a paper towel on the hose that comes out the door,when water comes out then you'll know it's melted out.hope this helps,one more thing if you blow the hot air up the tube where it goes into the door just keep an eye on the plastic tube you don't want to heat it up to much you can damage the tube so put hot air on and then hit another spot like after 30 or 40 seconds if you melt or dis form the plastic tube it might not reconnect into the fitting so watch it but it sounds like the board is bad.