Previous publishing request is in progress

We are using the iTunes U public site manager in Safari. About a month ago we created a new collection and attempted to publish. That collection never got published and, ever since then, when we go to publish any other new collection, when we click on publish, we get the message "Previous publishing request is in progress." Apple has been zero help so far, and we've been communicating for about a week. But we are not able to publish any new collections in iTunes U. Any help out there?