This is the mail system at host mail.dmsu.gov.ua.

I'm sorry to have to inform you that your message could not
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For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
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                   The mail system

<[email address]> (expanded from <[Державна міграційна служба України request email]>): host
    127.0.0.1[127.0.0.1] said: 550 5.1.1 <[email address]>: Recipient
    address rejected: User unknown in virtual mailbox table (in reply to RCPT
    TO command)