Planting group labels for shrub areas

I use a plant label that provides the QTY & square footage. When I use this with plant group label for shrub areas it provides the correct QTY & square footage, but whenever I want to run "verify labels" tool,
I've noticed the square footage amount will change to a single area amount on any of the group labels I have in the drawing. The quantity doesn't change, it still shows the correct quantity for the group. I attached 2 screen shots showing the before and after result when the "verify labels" tool is used.
Do you know why the square footage would change?
Thanks
Pat