eMail delivery failed: returning message to sender

I am getting the error below when sending to gmail accounts, i have talked to tech support and they have updated my settings on my account. Is there any thing else i can do?

    host gmail-smtp-in.l.google.com [142.251.163.27]

    SMTP error from remote mail server after pipelined end of data:

    550-5.7.26 Your email has been blocked because the sender is unauthenticated.

    550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM.

    550-5.7.26

    550-5.7.26  Authentication results:

    550-5.7.26  DKIM = did not pass

    550-5.7.26  SPF [harrellsmetalworks.com] with ip:

    [65.254.254.64] = did not pass

    550-5.7.26

    550-5.7.26  For instructions on setting up authentication, go to

    550 5.7.26  https://support.google.com/mail/answer/81126#authentication

af79cd13be357-8069806071bsi97593985a.161 - gsmtp