1 piece of laminate won't lay flat

This could be a number of things: There's a stone or nail etc under the floor that's popping it up. The floor has split through the center slightly causing the corner to lift up Some fast fit laminate flooring have plastic strips in the header joints, these sometimes come out of place and stick forwards slightly, stopping the neighboring from clicking down there is something inside the clicking tongue and groove which is stopping it going down The only right way to solve this problem would be to take up the floor to that point, investigate and possibly replace a plank or two. If you try and use wood glue/ super glue chances are it'll only temporarily fix it/ make it look worse/ make it harder to fix and repair properly.

One of the planks is damaged on the lock system by the sounds of it use a different board

Hi,unfortunately you need to replace floor board . Thanks

It will probably be that there is a slight separation fault (splitting)on the header (smaller) joint or the laminate board is not perfectly square. Another option could be that there is some debris stopping the board from locking in properly.