Authentication-Results-Original email header

The image you sent shows that your email is failing DMARC validation. This is likely because your tenant's DMARC policy is set to p=reject and your domain does not pass DMARC verification.

There are two things you can do to fix this problem:

1. Ensure that your domain passes DMARC verification. You can do this by checking your SPF and DKIM records and making sure that they are correctly configured. You can also use a tool like the Microsoft DMARC Record Generator to create a DMARC record for your domain.
2. Change your tenant's DMARC policy to p=quarantine. This will prevent your emails from being rejected, but they will still be quarantined and reviewed by Microsoft.

The articles Authenticate Outbound Email to Improve Deliverability - Microsoft Community Hub and Announcing New DMARC Policy Handling Defaults for Enhanced Email Security - Microsoft Community Hub state that Microsoft has rolled-out out new DMARC policy handling defaults to enhance email security. With the new policy, Microsoft will now reject emails that fail DMARC validation if the sender's policy is set to p=reject or p=quarantine.

This means that if you do not fix the problem with your DMARC validation, your emails will be rejected by Microsoft.

I recommend that you fix the problem with your DMARC validation as soon as possible. This will help to ensure that your emails are delivered to your recipients.