Subject: Undelivered Mail Returned to Sender
From: "Mail Delivery System" <[email-masked]>
To: <[email-masked]>
Date: Fri, 15 Mar 2024 00:49:49 +0330

This is the mail system at host mta652.syd.oss-core.net.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <[email-masked]>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<[email-masked]>: host
mailstore.service.int.oss-core.com[172.27.72.112]
    said: 550 5.1.1 <[email-masked]> User doesn't exist:
    [email-masked] (in reply to RCPT TO command)