My message notifications won't work on my new iphone 5c?

I got my new iPhone 5c 2 days ago and so did my mom. When she gets a text, it shows up either on her lock screen, or on a banner at the top of whatever page she is on, and makes her text alert sound. Mine doesn't do that and makes no sound. I can only see when I have a text message by opening my messages app. I can't figure out the difference between our two iPhones.

It broken