Not able to show data in combination chart

Hi Experts,

I am new to BO Design studio and I am facing some issues in beginning itself. My issue is, I have 12 months data for some KPI's and I need to show two KPI's values in a single chart(Combination or Dual axis).

In Initial view I have selected needed KPI's and measures

once inserted chart, in data selection I have selected only those two KPI's which i want to show in chart but when i select 2nd KPI's measures I am getting following error.

Am I doing in right way? Is there any other way to show two KPI's measures in combination chart?

Please help

Regards,

Mathivanan.M