Using Word 2002 on WinXP Pro

I've created a style to be applied at the beginning of a
new section. There is a number format within the created
style.

My problem is when I applied the style the numbering
works great, but when I edit the document, I go in
manually to start renumbering certain sections, it does
not work. Am I doing something wrong? Or do I have to
recreate a new style everytime I want to start
renumbering a section?

Thanks.