Thank you for confirming this. If you're using the PHP client library, you may refer to
this particular line of the code sample which retrieves all accounts that are directly under the manager account. Once the report definition is created, the reports will be downloaded for each account in the list. You may refer to the
iteration logic here for each report download under the manager account. For each successful report download, you will be able to
log the clientCustomerId associated with the report. You may refer to the PHP code sample
here as a reference. Let me know if you have any other questions.