Why don't emails go to gmail?

Question

gmail

Vps server with LAMP + sendmail
Letters addressed to gmail
Not sent and attacked in dead.letter
In the report I see
---- Transcript of session follows -----
... while talking to gmail-smtp-in.l.google. com.:
>>> DATA
<<< 550-5.7.1 [2a01:4f8:c0c:787b::1] Our system has detected that this message does
<<< 550-5.7.1 not meet IPv6 sending guidelines regarding PTR records and
<<< 550-5.7.1 authentication. Please review
<<< 550-5.7.1 https://support.google.com/mail/?p=IPv6AuthError for more information
<<< 550 5.7.1 . l10si5584580wmg.68 - gsmtp
554 5.0.0 Service unavailable

Registered in gsuit , trying to create a DKIM record but without success. Who faced this problem and how did you solve it?

Answer 1

DKIM in GSuite can only be created after three days. Can you test it on mail-tester.com and drop the link here?

Answer 2

abandoned this idea, set up work via the smtp protocol