Thats guaranteed its been opened.
My guess is they have removed the board to probably replace an LCD. Put it back together and bent a pin. They are very very small to see. You have to make sure you put them in dead straight. If it is right, the cable will find its own way in. Then just push it up until right in.
Best way to put the ribbon back is use your tweezers to almost curl the ribbon back a little... This will let the edge of the cable push its way in slightly when you release the tweezers. Then just tease it in.
There are tweezer marks on the ribbon too. There is no need to touch the ribbon cable like that. Lift the FPC lug and look for the edge "flaps" on the ribbon that butt up to the connector. Then tweezers either side, on the flaps either side of the connector and just hook it out on these flaps / tags whatever you want to call them. No need to pinch the cable.
This advice isn`t aimed at you! Just general observations I`ve made during the months ive been doing these pissing jobs.
