@20CenturyLights: The "The username you have entered is not a valid Etsy user" message almost always means that the account has been closed (either by the person or by Etsy - in this case probably the latter if a scammer). Just in case, try to mark the message as SPAM.
It's a good thing you can't reply. I've lost count of how many new sellers thought needing their email was legit, replied, then eventually, believing the scam to be legit. lost a lot of money.
