[Behsci] Mail delivery failed: returning message to sender

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: postmaster(a)stir.onmicrosoft.com host stir.mail.protection.outlook.com [52.101.68.3] SMTP error from remote mail server after RCPT TO:<postmaster@stir.onmicrosoft.com>: 550 5.4.1 Recipient address rejected: Access denied. [DU2PEPF0001E9BF.eurprd03.prod.outlook.com 2024-01-18T12:26:51.314Z 08DC14931A0D9CE1]