Unable to request a Certificate in AWS

To resolve the issue of your AWS Certificate Manager (ACM) certificate request timing out after 72 hours, you'll need to take the following steps:

1. First, delete the failed certificate request. In the ACM console, find the record for the timed-out certificate, select it, choose "Actions," and then "Delete."

2. After deleting the failed request, initiate a new certificate request by choosing "Actions" and then "Request a certificate."

3. When requesting the new certificate, pay close attention to the DNS validation process. ACM will provide you with CNAME records that need to be added to your DNS configuration. Since you're using Route 53, you should see a "Create records in Route 53" button in the console, which can automatically add these records for you, if the Route 53 hosted zone and certificate reside in the same AWS account.

4. If the "Create records in Route 53" button is not available, check the following:

   • Ensure you're logged into ACM and Route 53 using the same AWS account.
   • Verify that you have the necessary IAM permissions to create records in your Route 53 hosted zone.
   • Confirm that the domain is publicly addressable and hasn't been validated before.

5. If the Route 53 hosted zone isn't in the same AWS account, you should add the CNAME records manually. You should make sure to copy the record name and value accurately. Be cautious of any automatic modifications your DNS provider might make, such as adding trailing periods.

6. After adding the CNAME records, ACM will attempt to validate your domain ownership. This process should complete within 72 hours.

7. Monitor the status of your certificate request in the ACM console. If successful, the status will change to "Issued."

If you continue to experience issues, double-check that your DNS configuration is correct using tools like dig or nslookup. Also, ensure there are no Certification Authority Authorization (CAA) records blocking certificate issuance for your domain.

By following these steps, you should be able to successfully provision an ACM certificate for your public domain.
Sources
Troubleshoot certificate requests - AWS Certificate Manager
Resolve the ACM "validation time out" error | AWS re:Post
AWS Certificate Manager DNS validation - AWS Certificate Manager
Request a public certificate in AWS Certificate Manager - AWS Certificate Manager
Troubleshoot DNS validation problems - AWS Certificate Manager