Possible connection problem with LCD screen

My Laptops display randomly stops working when it is touched. The Display shows horizontal or vertical lines. When a light background is on the screen will turn light grey and when a dark background comes on the screen will turn dark grey.

Usually this problem can be fixed by nudging the screen but the problem has progressed to a stage where it cannot be fixed by a nudge.

Right now I am using an external monitor so this rules out problems with the computer.

I'm just wondering what I will be able to do to fix this problem.