Collaborator's dashboard

The system says:

Account Creation Failed
The email address you provided is already in the database.
Submit Contact Info

WTF?!? Of course its in the database!! Bottom line is I cannot even report the problem I'm experiencing, which is an important contact I invited to join my Linkedin Group cannot join the group because HIS EMAIL is already in the database. The message he gets, in red letters, is:

The email contactsemail@company.org is unavailable

What does he need to do to join? And what do I need to do to be able to post a question / request to Linkedin's help center?