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Navigate to the Ingestions list page (Admin > Ingestions > List).
Search of failed ingestions
Note: If the ingestion file still exists, then the file size cell for the given row will be populated.
Click the ID link for the ingestion that you'd like to alter.
Click the Cleanup Ingestion link in the sidebar to delete the associated ingestion file.
Note the success message and that the file size is no longer indicated.