External domain emails not reaching cox.net mailboxes.
I need to know who to report this problem to.
The school district I work for is having issues sending new emails to Cox.net customers. We have no issues with our reputation or being black listed. We use O365 exchange for our mail provider. They provided a trace log showing the email being delivered with no rejection. The senders receive no NDR's. The mail doesn't appear to be going to spam or automatically getting deleted.
If someone in the school district replies to a cox e-mail, that one will be successfully delivered to the Cox user.
I've chatted with support about this issue. They advised me to send an e-mail to email@example.com . I have sent three emails in the last week with no response.