You can use the same filed only once for a slicer because multiple/single selection in one slicer would affect the values in the 2nd slicer.
Instead, you can create a duplicate column for the same field and then put the slicer on the page to affect calculated columns.
To duplicate the column, go to Edit Queries, Right click on the column and change the name fo the column.
Now select those values from the actual field for one calculation and the duplicate field to add another slicer.
Hope it helps you.