Use this to request someone be added or removed from your workspace.
If you want to see who has access to your workspace, use this PowerBI report and search for your workspace.
https://app.powerbi.com/groups/61ba6365-7315-4253-89a2-8d896afb29d8/reports/0d1eb5b7-435e-49f5-9f0c-2136fa246db8/ReportSection?experience=power-bi