Words with Friends Contacts List

I am liking the Words with Friends app, but when I try to invite friends from my contacts list, why do only two people show up (and I am one of them)? It's like the app isn't detecting my contacts list correctly? Anybody else experiencing this, or have any suggetions?
Thanks!

I don't know. Most of mine show up, but not all.
Maybe reinstall the app.

I just went ahead and uninstalled it. I'll stick with Wordfeud; I like it better, anyway.