Not possible to send to gmail

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??????????????????The mail system

<jarosl*********@gmail.com>: host?gmail-smtp-in.l.google.com[108.177.15.26] said:
???550-5.7.26 This mail is unauthenticated, which poses a security risk to the
???550-5.7.26 sender and Gmail users, and has been blocked. The sender must
???550-5.7.26 authenticate with at least one of SPF or DKIM. For this message,
???550-5.7.26 DKIM checks did not pass and SPF check for [rainbowsongs.org]
???did 550-5.7.26 not pass with ip: [84.19.1.232]. The sender should visit
???550-5.7.26 ?https://support.google.com/mail/answer/81126#authentication?for
???550 5.7.26 instructions on setting up authentication.
???y7-20020a5d6207000000b0030922bb0e05si9118371wru.32 - gsmtp (in reply to end
???of DATA command)
Reporting-MTA: dns;?smarthost-dus.org-dns.com
X-Postfix-Queue-ID: 8FD54A0E8B
X-Postfix-Sender: rfc822;?[email protected]
Arrival-Date: Fri, 16 Jun 2023 10:33:15 +0200 (CEST)

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