You should be able to do it this way:
1. First add both columns to same section of Y-axis (select them both at the same time and drag and drop to Y-axis and select the visualization you want.
![jthi_2-1629044149947.png jthi_2-1629044149947.png](https://community.jmp.com/t5/image/serverpage/image-id/35029i3DF7E825F005FC9E/image-size/medium?v=v2&px=400)
2. Right click on graph and choose add to add the visualization you want (you can also shift click to select the visualization from the top of graph)
![jthi_1-1629044115394.png jthi_1-1629044115394.png](https://community.jmp.com/t5/image/serverpage/image-id/35028i34DECFC29E1570FB/image-size/medium?v=v2&px=400)
![jthi_3-1629044167406.png jthi_3-1629044167406.png](https://community.jmp.com/t5/image/serverpage/image-id/35030i9930569B8DC98282/image-size/medium?v=v2&px=400)
3. Then from the left of graph expand Variables menus and uncheck unnecessary columns
![jthi_4-1629044203633.png jthi_4-1629044203633.png](https://community.jmp.com/t5/image/serverpage/image-id/35031i48E125F752DB026C/image-size/medium?v=v2&px=400)
-Jarmo