The messages should displayed according to the following cases
1)User must select the sheet name
2) post selecting the sheet name and a message should pop up to saying KPI Description also be selected.
after selecting both of them the values should displayed
your condition should be
count(distinct sheetname)=1 and count(distinct kpidescription)=1
your message should be
if ( count(distinct sheetname)<>1 , 'please select a sheet name' ,
if ( count(distinct kpidescription)<>1 , 'please select a kpi'))
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