BTW, I think maybe your lists need 4 spaces before the second level, and maybe no newlines between items?

No, those are second level lists (under the numbering), so that's why are the empty ones. Deleting the sub-listing __ prefix makes numbering stop, adding additional two doesn't change anything

* thing 1
  * thing 1.a
* thing 2

• thing 1
  • thing 1.a
• thing 2