Either the polariser of screen is fractured (behind the black border at the bottom, so this won't be visible unless the screen is removed), or the ribbon where the screen PCB is soldered to the screen has slightly come away, so when moved the lines cut in and out.
Whichever issue it is, the only solution would be to replace the screen. The polariser is part of the screen, and the PCB is not soldered to the screen using standard methods (soldered the same way an LCD cable is soldered to an iPhone screen), so you would need a special machine to do this.