Outline Numbering

I am having a dunce day here. Hope someone can help.
I am writing an employee handbook and I can’t get the numbering correct. The main headings would be 1.0, 2.0 etc. Under 1.0 would be 1.1, 1.2, 1.3, etc. and 2.0 would be 2.1, 2.2., etc. The main headings are numbering correctly, the 1.1, 1.2, etc is showing up as 1.1, 2.1, 3.1 and I can’t do the next section at all without re-setting the numbering. HELP! I am sure I am overlooking something.