My iPhone says I have one unread message, but doesn't show anything? - 1

It says I have one unread message but when I click on it, it show nothing. Like none of my messages show up. Period. And after I look at a blank screen for a few minutes it just goes back to the home screen.

My phone does this everyday. Why I have to do it turn my phone completely off and count to 30 then turn it back on and then it just goes back to normal.

Restart your phone