Outbound email issues to Outlook hosted email

We are seeing massive amounts of the following errors pile up in our mail queues.

"452 4.5.3 Too many recipients (AS780090)"

This happens even when there is only 2 or 3 recipients. I think there may be a network issue at MS hosted email.

https://lists.ausnog.net/pipermail/ausnog/2023-October/threa...

https://www.reddit.com/r/sysadmin/comments/1755npg/anyone_el...