Not Receiving Emails from 1 Email Address

Not Receiving Emails from 1 Email Address

I have an email user that is not receiving email from 1 email address/domain.  This includes both his main email address and alias.  He can receive emails from other email address and domains.  The email address/domain he cannot receive emails is successfully emails to other email addresses.  He is able to send emails.

We have whitelisted both the email address and domain with no luck.  The sending email address is a no reply email.  I see no blocks, messages, etc.  The sender is an automated system and they said they do not have info to help.

Any help or ideas would be greatly appreciated.