Check logged user

mtzzwr - Sorry, not quite understanding this. You can use USERPRINCIPALNAME function to get the identity of the user. USERPRINCIPALNAME function (DAX) - DAX | Microsoft Docs

Not quite understanding things beyond that in terms of what you are trying to do.

mtzzwr 
You would need to use USERPRINCIPALNAME to perform a dynamic RLS. Please refer to the below link:
USERPRINCIPALNAME – show user name and use it in RLS (DAX – Power Pivot, Power BI) – ExcelTown – kurzy přesně pro Vás

Remember Report Server is not same as Power bi Service: Row-level security (RLS) in Power BI Report Server - Power BI | Microsoft Docs

Paul Zheng _ Community Support Team
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