If the "Select Accounts" dropdown doesn't seem to show all of Customer tenant accounts follow the below process:
- Select the master payer billing account in the 1st dropdown.
- Navigate to the second dropdown and accounts associated to this billing account will now appear
- Select all appropriate accounts
The First dropdown is to select the Billing Accounts and then, Second dropdown will show the AWS Accounts for the selected Billing Accounts. When we select the billing account first then all AWS accounts should be available in the second dropdown (as shown below):