Locate Instance

Hello,

Support will only be able to provide information of the account you have access to and where you open the case from as for security and privacy reasons, AWS Support can't disclose information from other Accounts. Here are few options:

1. If you have AWS CLI installed and configured, you can run the following script to get the Account where the Instance belongs: $ aws sts get-caller-identity --query "Account" --output text
2. In case CLI credentials are not configured, and since you can access the Instance via RDP, you can do a manual approach to deploy Ec2Launch and check the Instance ID and region if you configure the wallpaper to show such information (1). This will narrow it down to Availability Zone (thus the Region), Private IP as well so the CIDR would clue you in as to which of your Accounts have that range.
3. Alternatively, if the Instance is managed by SSM and part of an organization, you can use SSM to gather Inventory for multiple accounts and regions (2).

I hope the information above is helpful!

References (1) EC2Launch v2 settings - https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/ec2launch-v2-settings.html (2) Querying inventory data from multiple Regions and accounts - https://docs.aws.amazon.com/systems-manager/latest/userguide/systems-manager-inventory-query.html

I think it's best to contact AWS Support in your case.