Changing data source in pivot table- "Back" button is disable
 

I see lot of answers like Right Click pivot table then wizard then Back.

I have SQL server analysis services Cube in Excel using Pivot table I like
to change data source when I right click to pivot table and go to wizard the
Back and Next buttons are disable.

Whats a best way to change data source when you are accessing Cubes in Excel?

Thank you - Ashok