Please follow the instructions below to troubleshoot the TV...
Step 1: Unplug the TV cord from the power socket
Step 2: Leave it unplugged and while it's unplugged press and hold the Power button on the TV for 25 seconds
Step 3: Release the power button and plug the cord back in. Turn ON the TV using the remote control or manually and check if the lines on the screen are still visible
Note: IF the issue persists then please contact our Customer Support Team at 888-842-3577