CloudFront has detected the DNS record for the domain is misconfigured. The DNS record for this domain points to CloudFront's IP Range, but is not explicitly listed as an Alias for a CloudFront distribution, see Adding an Alternate Domain Name. Due to the misconfiguration we have detected within your DNS and the possibility of another AWS account's ability to utilize this domain name to serve malicious content, CloudFront has blocked this domain name from being used.
If you own this domain name and would like to associate the Alias to your CloudFront distribution, please follow the article here to get the Alias restored back to your distribution: https://aws.amazon.com/premiumsupport/knowledge-center/resolve-cnamealreadyexists-error/.