flag message folder

I can't find the flag folder in mailapp. It's a iPhone 4S and it have iOS6.

I can see it in my iPhone 5 and my iPad 2!

Don't now why I can't see it.

I can flag messeges but they don't merage in the flag folder! (Can't find/see it!)

I can see my other inboxes and the star folder, but not the flag!!!!