Delivery to the following recipient failed permanently:

Delivery to the following recipient failed permanently:

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for
the recipient domain grupoatitude.com.br by mx.zohomail.com. [72.5.230.114].

The error that the other server returned was:
554 5.2.3 MailPolicy violation Error delivering to mailboxes

Hi.
How do I fix this?