Send email pkp ojs3

It is happening that all communication in the workflow: acceptance of articles, sending to reviewers, launching the edition, etc., we are receiving errors.

Messages do not arrive in the email box of those involved.
I get the following in my main box:

host gmail-smtp-in.l.google.com [2607:f8b0:4002:c10::1b]
SMTP error from remote mail server after end of data:
550-5.7.1 [2a02:4780:2:8523::1] Our system has detected that this message does
550-5.7.1 does not meet IPv6 sending guidelines regarding PTR records and
550-5.7.1 authentication. Please review
550-5.7.1 Prevent mail to Gmail users from being blocked or sent to spam - Gmail Help for more information
550 5.7.1 . a4-20020a259804000000b0096a57993cbesi8983547ybo.542 - gsmtp
Reporting-MTA: dns; biofarma.med.br

Action: failed
Final-Recipient: rfc822;


Looks like a problem with google email.

Does anyone know how we can configure to get out of this error?