The problem I assume is somewhere on the MB as when I press in certain part of the MB then the keys are starting to work again. The keyboard is completely OK when you find the golden push point.
Note that I disassembled completely the MB so I am NOT just pushing on the case which can twist the keyboard flat cable or connectors.
Anyone faced something similar in some other or the same laptop ? Otherwise I would end up using a bluetooth keyboard but I would like to use the one that is in place