Hello,
Thank you for posting in Microsoft Q&A.
Based on the description, I understand your question is related to fetch Power BI Service audit logs using Search-UnifiedAuditLog cmdlet.
You need to have the Audit Logs role in the Security & Compliance Center and be a Power BI Service Administrator. Check that audit logging is enabled for Power BI in your organization. You can check this in the Power BI admin portal under Audit logs. Check the date range specified in -StartDate and -EndDate includes the period when the activities occurred.
Check if there are any errors or warnings that might indicate why the logs are not being returned after run the cmdlet.
You can also check more info in below link:
https://community.fabric.microsoft.com/
Have a nice day.
Best Regards,
Molly
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