Using sample snap to choose one person from each business unit

I am using the sample snap in a simple pipeline. I need for the sample to choose one person from each field called custom factor 6. I have 41 units there. here is the closest to what i need but i am expecting 41 rows. Can anyone help on this?
Using stratified sampling
pass thru at 0.005 (i have 12,000 employees)
random seed is unchecked.