COUNTIF counting blank cells with formula in it

I have a spreadsheet with a list of employee names, which are generated by a formula. I created a countif formula, but its counting the blank cells due to the formula within the cell, which is not what I want.

For the formula, if the name does not have a duplicate, then the cell should be blank. But if there is a duplicate, list the instance in numeric order. For instance, George has duplicates within the range so for the first Geroge instance, the formula would provide a 1 and for the next George instance, it would provide a 2.

Spreadsheet attached to show the above more clearly.

=IF(COUNTIF($A$2:$A$10,A2)>1=TRUE,COUNTIF($A$2:A2,A2),"")

Thank you!