Storage lens not showing prefix report

There are a few potential reasons why you're not seeing prefix-level metrics in your S3 Storage Lens dashboard:

1. Ensure you've enabled advanced metrics: Prefix-level metrics are part of S3 Storage Lens advanced metrics. Make sure you've upgraded to advanced metrics and recommendations in your dashboard configuration.

2. Check your prefix configuration: Verify that the prefixes you've configured match the structure of your bucket contents. If no objects match the filters you've included in your prefix configuration, no metrics will be generated.

3. Verify data availability: It can take up to 48 hours for new metrics to appear after configuring or updating a dashboard. If you've recently made changes, you may need to wait a bit longer.

4. Examine your filters: If you're using Storage Lens groups in addition to prefixes, be aware that the Prefixes filter and the Storage Lens groups filter cannot be applied simultaneously. Make sure you're not accidentally filtering out your prefix data.

5. Check your metrics selection: Ensure that the specific metrics you're interested in (like GET requests) are selected for prefix-level aggregation in your dashboard configuration.

6. Verify permissions: Make sure you have the necessary IAM permissions to view the S3 Storage Lens dashboard and the specific metrics you're interested in.

If you've confirmed all of these points and are still not seeing prefix-level metrics, you may want to double-check your overall dashboard configuration or contact AWS support for further assistance.
Sources
Amazon S3 Storage Lens now aggregates activity and status code metrics by prefix
Viewing S3 Storage Lens metrics on the dashboards - Amazon Simple Storage Service
Viewing metrics with Amazon S3 Storage Lens - Amazon Simple Storage Service
Visualizing your Storage Lens groups data - Amazon Simple Storage Service