lapbook, screen does not work

good evening
i have a 15.6 lapbook with z8350. working.
the zipper broke.
I opened the lapbook, unplugged the 15.6 monitor and connected to an external monitor. but it does not work. why?
I tried to plug everything back in and now the proprietary 15.6 monitor doesn’t work either. is there a power saving protection?
how do i get files inside?
i also tried to unplug the battery for hours and reconnect