Vertical stripes on screen. Hi.This Tv displays fine except for 2 vertical lines running down the

Question

Hi.This Tv displays fine except for 2 vertical lines running down the right hand side of the screen. The lines are around 1 inch wide each and show a mirrored image of whatever is showing on the screen. I've been searching for a service manual for this particular tv to try and get into the service menu but so far had no luck.Any ideas please.