A common error is to believe that chapter numbering is the same as list numbering. Though the basic mechanism is the same, many things happen behind the scene to create an outline and a TOC.
In your attempts to twist your numbering, you created an awful mess and caused confusion in Writer with a conflict between chapter and list numbering.
The Heading n family is associated by
Chapter Numbering with a reserved numbering style. You overlaid it with direct formatting and now you have two numbering active on Heading 1 to 3.
Heading 4 is different. Among your attempts, you removed Heading 4 from the
Chapter Numbering hierarchy, leaving only the list numbering you added with direct formatting. In addition, you changed the font face in paragraph style Heading 4.
You have damaged your style dictionary beyond your purpose. Since you probably don’t know what you’ve done, I suggest you restart from a fresh blank document and paste your old text as Unformatted text. Then apply the desired styles, notably the Heading n family to your outline. When done, customise
Chapter Numbering to get your expected numbering.
Golden rule: never mix list and chapter numbering. They look the same but are two different logical features.