Problem on 'homie'?

There is a major problem going on (but definitely not for all users), we have lost all our domains, and all of our users from the panel. However, the web sites work, and we can ftp to them. Mail can be sent, but any mail coming in gets bounced back to the sender. No response from support yet.
I suspect the system 'homie’
Postfix program at host reports that the user it expands my email to does not exist. This has worked fine for 4 years, so the problem is over there.