Make the call and hope it's in warranty. Let the tech diagnose it but to me it sounds like a panel issue.
We recently started to notice on our LG OLED55B6P that the color yellow in the middle of the screen shows up as highlighter green. As it moves to the edges the color is yellow as it should but green in the middle. Today on certain color backgrounds there are black squiggly lines that appear in the middle. When I pull up a blank yellow/orange/blue screen you can clearly see that the TV is normal in the corners and is off color in the middle with black portions all through out the middle of the TV. Is this screen burn or a different issue?