Blinking Red Border around my screen appeared and it won't go away. What can I do?

[StrikeSniper]

Blinking Red Border around my screen appeared and it won't go away.

After viewing aYouTube video (I think) my Samsung Galaxy S7 developed a blinking red frame around the edge of the screen. It looks like a photo frame. I'm worried someone has access to my screen data. I would hate to do a factory reset. Has anyone else had this happen to them and if so how did you get rid of it (if you did). I GOOGLED it and there are other users that have had this happen but the latest I saw was a Galaxy S3. Thanks. I appreciate anything.
Ricky

 

[H3aTeRzz]

Re: Blinking Red Border around my screen appeared and it won't go away.

Enter safe mode, and see if it still occurs....let us know.

 

[RicKaysen]

did you, at least, power down and restart to see if it stops?