We are aware of an issue with the Teams Usage Report not producing accurate data in Portal.
Although this report appears downloadable from Portal, we have stopped the job that refreshes the data whilst it is actively investigated by developers.
Latest Updates and Guidance:
This is being investigated under problem record PRB0206639.
The Teams Usage Report can be produced manually upon request; therefore, Administrators should raise a Service Request with the helpdesk (firstname.lastname@example.org), referencing the Organisation they require the report for, along with the problem record.