Blueprint mandatory follow up task problem

Blueprint mandatory follow up task problem

I have a stage for a lead called "contact in future".  If the agent chooses that stage I would like it to not only make notes mandatory but also create a follow up task.  I am able to click on the "during" and "+add" and then "associated items" tasks BUT when I try to make the task or call mandatory with validation rules it does not work.  They can leave a note and totally ignore the follow up task portion and the system does not give a warning and lets them continue.  Any one have an idea on this?