[Plugin: Simple facebook connect] problem to post my article on fan page!

Hi, i have a problem with the connection with my fan page.

I paste my fan page id in “facebook fan page” input but when i try to post my posts, after the click on “Publish on facebook fan page”, appeare a facebook error:

API Error Code: 102
API Error Description: Session key invalid or no longer valid
Error Message: Iframe dialogs must be called with a session key

Why?

This is a clear installation, there aren’t old version or other plug-in.

I think that the problem is in my facebook app but i don’t know what are the corrects settings.

can you help me?

Thanks !