When you try prophets, but they're not there.
1. Your code looks fine. Really, it does.
2. You've checked the documentation, but it's just not cooperating.
3. You've tried debugging, but it's just not debugging.
We've diagnosed you with a bad case of Null-Pointer-Exception-itis. Don't worry, it's highly contagious, and we're sure you'll recover with a little TLC.