constantly getting a false 552 when sending email containing a particular domain name via Plusnet mail relay from our mail servers. I don't see anywhere to report this directly or white list. All the support links seem to relate only to incoming not outgoing traffic?
host relay.plus.net[18.104.22.168] said: 552
Zp3N1u0051uUjak01p3P5a message rejected due to spam or virus. If you
believe this is in error please login to your portal or contact your ISP
support team. (in reply to end of DATA command)