Cant receive emails via gmail

Cant receive emails via gmail

I setup custom zoho email few hours ago. I am not receving emails from gmail accounts for some reason but its fine when I use other email clients. I get this error:

The error that the other server returned was:
550-Please turn on SMTP Authentication in your mail client, or login to the
550-IMAP/POP3 server before sending your message.   mail-qg0-f44.google.com
550-[209.85.192.44]:45963 is not permitted to relay through this server without
550 authentication.

Kindly help