I was unable to open the workbook you attached.
However i recreated it using the same data source.
Not 100% sure this is what you were trying to do but I created (2) separate calcs for MIN SALES and MAX SALES.
I brought both rows shelf, opened the drop-down selection box on the MIN SALES pill and selected Dual Axis.
The plot shows both MIN and MAX simultaneously.
Book1.twbx 1.4 MB