This is the mail system at host cyber-security.ga.
I'm sorry to have to inform you that your message could not
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If you do so, please include this problem report. You can
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The mail system
<email@example.com>: host mx1.zenbox.pl[188.8.131.52]
said: 554 5.7.1 <firstname.lastname@example.org>: Recipient
address rejected: SMTP AUTH is required for users under this sender domain
(in reply to RCPT TO command)