Me.com problems receiving email

My apple account is working fine

i have generated an app specific password for my external email app.

i can send emails to any external account

but I have a problem receiving messages to me.com specially from my email system riti.org

And I receive messages like the enclosed....

please advise

==========================

“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:

   (ultimately generated from )

   all hosts for '' have been failing for a long time (and retry time not reached)”

[Personal Information Edited by Moderator]