headings level word 2007

i have a little problem with headings level
i defined 3 headings level
level 1 is writing 1, 2, 3.....
level 2 is writing 1.1, 1.2, 1.3.....
level 3 is writing 1.1.1, 1.1.2, 1.1.3....
i must write so
1
2
3
4
5
5.1
5.2
5.3
6
7
7.1
8
8.1
8.1.1
8.1.2
9
10
11
my problem is begining on 5.1 because it is writing 1.1 instead of 5.1
when i define it as first number 5.1 it occur a problem on 7.1 because it is
writing 5.4 instead of 7.1.
is there a style in this wise? or imagine i it?

The first thing to try, assuming that you have properly linked the numbering
to heading styles, is select the problem paragraphs and pressing Ctrl+Q (to
reset paragraph formatting to style).

If the above doesn't help, or if you haven't attached numbering to styles,
do the following to quickly apply numbering to your headings: Click the Home
tab, and then click Multilevel List. Under "List Library," choose the "1
Heading 1 1.1 Heading 2 1.1.1 Heading 3" format. Apply the headings to the
relevant paragraphs of text.