This is the mail system at host ip-172-30-1-231.ap-northeast-1.compute.internal.

I'm sorry to have to inform you that your message could not
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The mail system

<idolpm@gmail.com>: host gmail-smtp-in.l.google.com[142.251.8.27] said:
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 [pm.fdol.jp] with ip:
[52.199.239.196] = 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
41be03b00d2f7-aee7deaf320si7864314a12.332 - gsmtp (in reply to end of DATA
command)