Tiered Numbers not working in Pages version 13.2

I'm trying to create a Table of Contents in Pages 13.2, on an updated Macbook Pro 2018 laptop, and although I have followed the steps to check Bullet & Lists/Numbers/Tiered numbers - the only list I can create simply advances 1, 2, 3. I have watched videos, read other queries - not finding any help.

Is there a secret to making this thing work? It shouldn't be this mysterious.