We are not getting any mail on this mail (fiatpayments)

If you're no longer receiving emails on your fiatpayments domain when you previously were, there are several potential causes and steps you can take to troubleshoot the issue:

1. Check your MX (Mail Exchanger) records: Ensure that your domain's MX records are correctly configured and pointing to the right mail server. Incorrect or missing MX records can prevent email delivery.

2. Verify your domain and email settings: If you're using Amazon SES or WorkMail, make sure your domain and email addresses are properly verified and set up in the service.

3. Review your inbound mail rules: Check any inbound mail rules or filters you may have set up, as these could be inadvertently blocking or redirecting incoming emails.

4. Check spam folders: Ensure that the expected emails aren't being filtered into spam folders.

5. Examine DMARC settings: If you have Domain-based Message Authentication, Reporting, and Conformance (DMARC) policies in place, review them to make sure they're not causing legitimate emails to be rejected.

6. Look into any recent changes: Consider any recent modifications to your email setup or DNS settings that might have affected email delivery.

7. Enable logging and message tracking: If you're using a service like Amazon WorkMail, you can enable message tracking to help diagnose delivery issues.

8. Check for greylisting: Some ISPs use greylisting to combat spam, which can cause temporary delivery delays.

If you've gone through these steps and are still experiencing issues, it would be advisable to contact your email service provider's support team for further assistance. They can help investigate any account-specific issues that might be preventing email delivery.
Sources
Mail routing - Amazon WorkMail
Emails not recieving to the sender domain in my PROD Amazon SES | AWS re:Post
Workmail not receiving mail | AWS re:Post