Mail box created but mails not receiving

Mail box created but mails not receiving My Domain plotsnow.com

Error:

The response from the remote server was:

550 5.1.1 <sales@plotsnow.com> Recipient not found. <http://x.co/irbounce>

Final-Recipient: rfc822; sales@plotsnow.com
Action: failed
Status: 5.1.1
Remote-MTA: dns; smtp.secureserver.net . (68.178.213.203, the server for the
domain plotsnow.com .)
Diagnostic-Code: smtp; 550 5.1.1 < sales@plotsnow.com > Recipient not found. < http://x.co/irbounce >
Last-Attempt-Date: Thu, 14 Sep 2017 09:48:27 -0700 (PDT)