won't power up after being off.

Have a RCA Smart TV won't power up after being off. Says no signal, then goes to white screen with a slight black line on the far left of screen. If I reboot my provider everything is perfect clear as pic and works perfect. Until I turn it off again. If I unplug it and plug it back in I get the the same result works perfect. Update is current, tried a different cable box, tried a different cable box not the issue.