Why doesn't the screen staying on when I get a text?

[AC Question]

Screen not staying on when I get a text.

When I get a text message or some other notification and the screen is off, I expect the screen to turn on so I can see the notification/text and then for it to turn off after 30 seconds (or whatever time I set). But whenever I get a notification, it flashes the screen on for a second and then it turns off, not giving me enough time to see the content. I have the screen timeout at 30 seconds and I have my settings on the "Show Content" on my lockscreen option when I get a notification. Any help?

-Cesar