Subject: Mail delivery failed: returning message to sender

From: Mail Delivery System <[email-masked]>
Date: Sun, 14 Sep 2025 23:15:04 -0700

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  [email-masked]
    host locum-se.mail.protection.outlook.com [52.101.73.22]
    SMTP error from remote mail server after sending data block:
    554 5.4.14 Hop count exceeded - possible mail loop ATTR34 [AMS0EPF00000190.eurprd05.prod.outlook.com 2025-09-15T06:15:04.221Z 08DDF25C92F4696E]