i found many emails name is showing unknown from usage report.
Where did you check this usage report? Teams admin center or Office 365 admin center?
If you are Microsoft 365 global administrator with Microsoft 365 Business subscription, you could try to change the setting in Microsoft 365 admin center:
- Go to the Microsoft 365 admin center.
- Go to Settings > Org Settings > Services.
- Select Reports.
- Clear Display concealed user, group, and site names in all reports, and then select Save.
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