1/6 of my screen is flashing with different size pixels

Hi, I have a MacBook Air, date 1/18/2023. I was working on the Mac when I noticed a vertical (top to bottom) rectangular darkened area on the far right of my computer, kind of like an overlay/curtain . Then it went darker and started flashing multicle colored columns of pixels. I can't add a video of it so you can't see it in action. ---The software is current on the Mac. -- I did notice when I rebooted it appeared one of my email accounts was not closing, etc., but I don't know that that has anything to do with it. I have rebooted the mac several times. At one point it did stop flashing and only the pale colored curtain remained, but it eventually came back while I was typing on the Mac. The unit is no longer under warranty, etc. So I am starting here with the troubleshooting, before proceeding to live customer support help for a fee.