I think the message speaks for itself on this one.
The maximum limit of Chatters has been reached and there's no spot left for anyone else.
If this is as in there's no spot left, or that our subscription to the chat service needs to be renewed, I'm not sure. But I'd say the chat is simply full right now because of the users having issues with FH.
If this stays for several days, feel free to let us know.
