Hi @Merlin1,
In the Dataverse tab, you can select details of a particular environment and see the breakdown of File usage per table. Things like Web resources (e.g. JavaScript, HTML, CSS, png), Solutions, asynchronous jobs, etc will consume file storage in addition to notes and attachments.
More information is documented here. Do be aware that it can take up to 24 hours for the storage to be reflected correctly in the admin portal after you've cleared out data.
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