Why is there a bright light on my screen?

[Android Central Question]

When l lower my brightness as low as possible the bottom of the screen will show me a bright light that glitches around crazy. There are no cracks on the screen but l got it used and it was already like this when l got it

 

[Morty2264]

Welcome to Android Central! What kind of phone do you have and how long have you had it? If you can return it or exchange it, I would recommend doing that.