How old is the television? Because of its new I would take it back or RMA it. If it doesn’t look good and work right out of the box then it’s broken. If this just happened it could be the backlighting other things
Are you plugged into a media streamer? You might try playing video games and seeing if the video looks good on that as a test or some other streamer. Like if you’re plugged into your cable box and it’s doing that but you switch inputs and it’s fixed and you know it’s your cable box or maybe that inputs components