Did any moisture get on the screen, such as window cleaner, coffee, etc?
You might need to disassemble the flip screen and clean the flat connectors. There is a how to post, because mine and somebody else's screen kept opening and closing. Mine started doing that right after I sprayed windex on it.
I suppose it is possible a harness has come off behind the cover. Not sure what the tech terms are for these. Not hard to pull the cover off to take a peek.