Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Fri, 3 Oct 2025 06:31:27 -0500

The original message was received at Fri, 3 Oct 2025 06:31:26 -0500
from m0440770.ppops.net [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 5.4.1 Recipient address rejected: Access denied. For more information see https://aka.ms/EXOSmtpErrors [BL6PEPF00020E63.namprd04.prod.outlook.com 2025-10-03T11:31:27.443Z 08DE00CA46F6207B])

   ----- Transcript of session follows -----
... while talking to afamilylegacy-com.mail.protection.outlook.com.:
>>> DATA
<<< 550 5.4.1 Recipient address rejected: Access denied. For more information see https://aka.ms/EXOSmtpErrors [BL6PEPF00020E63.namprd04.prod.outlook.com 2025-10-03T11:31:27.443Z 08DE00CA46F6207B]
550 5.1.1 <[email-masked]>... User unknown
<<< 503 5.5.2 Need rcpt command [BL6PEPF00020E63.namprd04.prod.outlook.com 2025-10-03T11:31:27.443Z 08DE00CA46F6207B]