Probably the door lock or maybe just the screws holding it in place...
The door switch is 11$ part on the sears parts website.
It is located in the control panel and seems to be just screwed into place.
Though it is not the exact same model it's the same base machine, so steps should be pretty much the same to this:
There are 2 switches there, not quite sure why and if you need to replace both.
But I would start with checking if the current switch is screwed into place properly.
If you have bad luck you might have worn out the holes it screwes into.
It screwes into plastic and from what it looks like and if you wore out those holes you either have to get creative in repairing them or you have to replace the plastic facia.
The door switch (not the latch) is pretty cheap:
https://www.searspartsdirect.com/product/3w62jg545p-0022-363/id-wd21x10224
The door latch has a plastic front piece and is pretty cheap as well, might want to check if that is worn out:
https://www.searspartsdirect.com/product/11xcz52yu8-0022-363/id-wd13x10019
If you really have bad luck and the front facia has worn out screw holey and you can't find a way to fix it, that part is somewhat more expensive since it includes the entirety of the facia, the interface and the lock mechanism at over 200$:
https://www.searspartsdirect.com/product/3tygkffwx7-0022-363/id-wd34x11275
Though honestly: If you can fix those plastic things those fixes usually only last a verry short time and before throwing 200+$ at a pretty basic lower quality machine, considering replacing it might be worth athought.
Way less likely but still possible would be the control being wonky, that would come in at 135$:
https://www.searspartsdirect.com/product/ebv4exy3bj-0022-363/id-wd21x10247
Main linke below to the sears part source, they have a nice easy interface to find parts!
And for price comparison just copy the the part number and google it, just as a tip.
GE GLD4460N10SS dishwasher parts - manufacturer-approved parts for a proper fit every time! We also have installation guides, diagrams and manuals to help you along the way!
www.searspartsdirect.com