Hi,
Please provide more details on the issue, which domain you are using to send is it personal or gmail or outlook? In my experience Outlook.com blocks the sending of email messages if the content looks like junk or spam if they are detected by the junk filters. Occasionally, emails that are legitimate are marked as junk. If your email message has been blocked, try changing the content of the email and attempt to send it again.
Hope this helps.
JS
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