Troubleshoot DMARC issues
If valid outgoing messages fail DMARC
- Check the SPF and DKIM settings for your domain, and make sure outgoing messages pass SPF and DKIM authentication. ...
- Check the DMARC policy and alignment settings for your domain. ...
- Check your DMARC daily reports to identify which outgoing messages don't pass SPF, DKIM, or DMARC.