Your message wasn't delivered to admin@pitts.in because the address couldn't be found.
The response from the remote server was:
550 5.1.1 The email account that you tried to reach does not exist. Please try double-checking the recipient's email address for typos or unnecessary spaces. Learn more at https://support.google.com/mail/?p=NoSuchUser 65si4748390itg.51 - gsmtp
Final-Recipient: rfc822;
admin@pitts.in
Action: failed
Status: 5.1.1
Remote-MTA: dns;
aspmx.l.google.com. (2607:f8b0:4001:c03::1a, the server for
the domain
pitts.in.)
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. Learn more at
550 5.1.1
https://support.google.com/mail/?p=NoSuchUser 65si4748390itg.51 - gsmtp
Last-Attempt-Date: Thu, 23 Mar 2017 02:54:12 -0700 (PDT)