SSAS Tabular has a limitation: It doesn’t allow dimensions to play multiple roles.
A common scenario is you have an order with multiple date: Call Date, Order Date, Ship Date, etc.
Adding multiple date dimensions in SSAS Tabular is not intuitive:
First you need to import the date dimension multiple times, and make sure you rename it to the appropriate.
Second: If you try to flag the second date dimension, sometimes it will not succeed. So in order to flag a second date dimension, switch from the diagram view in SQL Server Data Tools into the Grid view, select your date table, then from the menu bar, select Table > Date Dimension > Mark As Date Dimension > Then choose your date key which should be of Date/Datetime data type.
Then you will be able to see it in the visualization tools, such as Excel Pivot Table. Add a pivot table > select it > From the menu bar > Select Analyze > Add Timeline Slicer > You will see multiple date selectors: