If the status is Verification timed out
Domain verification will fail 72 hours past when requested, and the domain cannot be assigned to site.
Remove verification time out domain then re-register and verify it.
Also, check another document for troubleshooting on domain validations.
If "CNAME is used by other CDN"error occurred when you're attaching domain name to your site
If you get the following error: " used by other CDN", it means you cannot assign that domain to your account because it's currently used by another Amazon Web Services (AWS) account.
This could also include other products which are built on top of AWS.
- Detach that custom domain from another CloudFront Distribution you manage
- Locate the previous used service associated with that custom domain and remove/delete it
- Disable Webhosting on S3
Your AWS S3 may use it as a its bucket name with Website hosting enabled.
For more details, please check AWS' official documents: