Ultimate Facebook doesn't auto-post anymore


I installed Ultimate Facebook with using a few options including auto-post entries to a Facebook fan page wall. This works a few days very well. But suddenly the auto-post were not sent anymore.

I posted the entries using the "publish later" option of Wordpress. I defined the date and the time and all works well. Yesterday the auto-posting stops. The error logs are empty, the notices stored until the last successful auto-post.

I created a new FP app, but now change in (failed) auto-posting.

What can I do?

Thanks in advance.