Reporting-MTA: dns; server.dns-principal.com

Action: failed
Final-Recipient: rfc822;brittney.horder@gmail.com
Status: 5.0.0
Remote-MTA: dns; gmail-smtp-in.l.google.com
Diagnostic-Code: smtp; 550-5.1.1 The email account that you tried to reach does not exist. Please try
 550-5.1.1 double-checking the recipient's email address for typos or
 550-5.1.1 unnecessary spaces. For more information, go to
 550 5.1.1  https://support.google.com/mail/?p=NoSuchUser s129-20020a0de987000000b0061bca1c6f7esi369259ywe.401 - gsmtp