Press and hold the Power button on the TV remote until the TV turns off and back on
Unplug the TV power cord from the wall outlet
Wait 30 seconds
Plug the TV power cord back in
Press the Power button on the remote or TV to turn it on
If needed, press and hold the Power button on the remote for about 5 seconds to force a restart
For a soft reset, go to Settings > Support > Device Care > Self Diagnosis > Reset
Enter the PIN if prompted
Confirm the reset and let the TV reboot