A client may request a copy of the data you keep about them. WHMCS facilitates this via a client data export report:
1. Click the Reports tab
2. Under the Exports heading, click the Client button
3. Use the Choose the client to export field to search for the client in question
4. Use the checkboxes to select precisely what data to include in the export.
5. Once a client and at-least one export option is selected, click the Generate and Download Export button
This will generate a JSON file containing all the selected data for the client, which can then be supplied to them.