Try this
Are you seeing duplicate images on every channel?
➔ Go to [Settings] and start [Picture Test] to check if the picture works normally.
Running [Picture Test] in the Settings menu
WebOS 5.0
[2020 WebOS 5.0] Press the 
button on the TV remote and select [All Settings] → [Customer Support] → [Additional Settings] → [Picture Test].
Turn on the TV and press the [Settings] button on your TV remote.
Select [All Settings] in the [Settings] menu.
Select [All Settings] in the [Settings] menu.
① Select [Customer Support] and then ② [Additional Settings].
③ Select [Picture Test] in [Additional Settings].
Perform [Picture Test] to check the screen condition.
[Prior to 2019] WebOS
[2019 WebOS or before] Press the 
button on the TV remote and select [All Settings] → [Customer Support] → [Additional Settings] → [Picture Test].
Turn on the TV and press the [Settings] button on your TV remote.
Select [All Settings] in the [Settings] menu.
Select [All Settings] in the [Settings] menu.
① Select [Picture] and then ② [Picture Test].
Perform [Picture Test] to check the screen condition.
If the test picture is displayed normally, it is likely that the broadcast signal has a problem.
If the problem does not occur in the picture test, please contact the set-top service provider. (e.g., cable TV, Skylife, IPTV)
If the problem persists in the picture test, please contact LG Electronics Service Center.
This guide was created for all models, so the images or content may be different from your product.
