I'm writing a report and I have some problems with headings. I have this structure:

Chapter 1(heading1)
1.1(heading2)
1.1.1(heading3)
1.2(heading2)

Chapter2(heading1)
2.1
2.2

The problem is that when I choose heading 1 word writes a number before chapter -> 1 chapter 1 I want numbers to appear only from heading 2. I managed to change it using multilevel lists but it doesn't update appropriately. I mean I removed the number before chapter 1 for example but it did not update chapter 2 subheadings that became numbering from 1 (not 2). Please help me out. thanks.