Mail not reciving

Mail not reciving

Hi 

Recently setup mail for our domain name.

We are receiving every mails but not Gmail. Please find following error text . 

Failed to receive mail from Gmail and many people are using GMAIL. So Kindly suggest alternate way for the same. 


____Please find following error text . ________
The response was:

550 Please turn on SMTP Authentication in your mail client, or login to the IMAP/POP3 server before sending your message. mail-io0-f180.google.com[209.85.223.180]:48209 is not permitted to relay through this server without authentication.

Final-Recipient: rfc822;  x yz@xyz.com
Action: failed
Status: 5.0.0
Remote-MTA: dns; xyz.xyz.com  (108.179.246.62, the server for the domain.)
Diagnostic-Code: smtp; 550-Please turn on SMTP Authentication in your mail client, or login to the
 550-IMAP/POP3 server before sending your message.   mail-io0-f180.google.com
 550-[209.85.223.180]:48209 is not permitted to relay through this server
 550 without authentication.
Last-Attempt-Date: Mon, 25 Sep 2017 05:26:59 -0700 (PDT)
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