Hi,
Do you see the lines in BIOS as well? Try and boot the laptop into BIOS and see if the lines are still preset because if they are that means it's a display problem and you'll need to contact the manufacturer for them to repair or replace the display itself. To sure it's a display problem connect an external monitor if available and see if you'll those lines because if you do that's a graphics card problem and you'll still need to contact the manufacturer.