If faces near the centre of your OLED TV have a green hue this is due to the red pixels there having darkened simply through use over time.
Don’t bother running the many colour changing patterns on YouTube to fix this. It won’t. Try to progress a warranty repair however if that fails or while it is progressing you can change 3 picture settings in under a minute to improve the picture appearance considerably.
Change colour temperature to cool, increase colour and reduce tint (the balance of green to red). I show this on my Panasonic TX-55EZ952B in this #short video.
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