Locate account details for DNS hosting

Hello.

Do you know all of the AWS accounts your client owns?
Alternatively, if you have billing information, you may be able to identify the domain information by checking the invoice to see which AWS account is incurring Route 53 charges. https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/billing-pref.html

if you looking anything that can help, start with Checking WHOIS information to identify the registrant's contact information. When a domain uses Route 53, it will have AWS name servers in the format ns-xx.awsdns-xx.org, ns-xx.awsdns-xx.com, ns-xx.awsdns-xx.net, and ns-xx.awsdns-xx.co.uk. Confirming these will validate the domain is indeed using Route 53. After that you can use tools like dig, nslookup, or online DNS lookup services to query common record types (A, AAAA, MX, CNAME, TXT, etc.) to build a partial picture of the zone. Lastly, Work with the client's IT department since AWS accounts are typically tied to organizational email addresses, someone within the client organization might have access to the email that receives AWS notifications for the account.

You can also create a case to AWS support and follow these steps : https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/domain-contact-support.html