The License Usage report in Combine will display UPN information for each license however, if you would like this to display user information, the option must be enabled within M365.
Microsoft's guide to modifying UPN to display user information
Global administrators can revert this change for their tenant and show identifiable user information if their organization's privacy practices allow it. It can be achieved in the Microsoft 365 admin center by following these steps:
- In the admin center, go to the Settings > Org Settings > Services page.
- Select Reports.
- Checkmark the statement in all reports, display de-identified names (display anonymous identifiers) for users, groups, and sites, and then save your changes.
Enable Microsoft 365 usage analytics
Please be aware that Combine can take up to 24 hours to refresh M365 data.