I have Xeams set up as an email server.

All looks to be ok - but I have items in the OutboundAuditTrailFailure.log which I don't understand as I haven't sent any emails to this address.

All the emails in this list are inbound messages.

2019-07-24 18:35:02,896 - [      2343] 104.47.8.36,yyyyy@skiline.co.uk,,1924,[Failure reason: Unable to send email to the server. 
550 5.7.606 Access denied, banned sending IP [81.109.182.231]. To request removal from this list please visit https://sender.office.com/ and follow the directions. 
For more information please go to  http://go.microsoft.com/fwlink/?LinkID=xxxxxx (ASyyyyyyyy) [AM5EURiiFTiii.eop-EURii.prod.protection.outlook.com]
],Subject:  Delivery Status Notification(FAILURE)

I am pulling in emails using POP3 fetcher and delivering to a local email address not available to the outside world.

Hope someone can help.

M