Help with registering as micro entrepreneur - specifically health insurance!

Hello

I’m just trying to register as an autoentrepreneur. With the help of https://foreignersguidetofrance.wordpress.com/tag/auto-entrepreneur/ I got most of the way through but got stumped on the health insurance bit. Then I found this website and everyone seems incredibly knowledgeable! I followed the instructions of putting sans assurance but didn’t get the expected drop down menu. Can anyone help?
I’m using the cfe.urssaf website to complete the form.

Any help gratefully received!

Karen