Lighter stripe across top of screen?

[Android Central Question]

My Samsung S7 suddenly started getting a lighter stripe across the top, covering the notification area and a little bit more. It went away when I restarted a couple of times but this last time, restarting didn't work. Any idea about what is going on would be helpful. This is my third Samsung S7- they had to replace it twice due to other issues so I'm not looking forward to going the insurance route again if I can help it.