According to the state of the style dictionary, your statement is wrong. It has been manipulated (perhaps created) with M$ Word and chapter numbering has even been customised for some now unkonwn purpose. This customisation is responsible for the current state of affair.
Due to previous saves in DOC(X) format and multiple edits in LO before storing as .odt, your document is now damaged beyond repair.
Ideally, you would delete all WW8xxx list styles, but you can’t do it because these styles are in use and LO doesn’t allow it to avoid data loss.
What “proves” (logically wrong) numbering customisation is the fact tact that Heading 3 is not attached to Tools>Heading Numbering and has received a specific direct-format list styles (and sine list styles don’t exist in Word, I let you imagine the mess this creates).
A possible tedious manual procedure to fix your headings is as follows, but be aware that all headings must be cured, even those apparently good:
- put the cursor in a heading
- press Ctrl+0 (digit 0) to turn the heading Body Text
- press the numbering toolbar button to toggle off numbering
- press Ctrl+“level” to re-tag the paragraph as a heading (level= 1 for level 1, 2 for level 2, etc.)
Don’t forget to reconfigure Tools>Heading Numbering to include back the Heading n levels your discarded.
The above procedure is only a quick’n’dirty workaround to fix the issue with headings. It does not solve the general (bad) formatting of the document. There are wy too many direct formatting, such as manual page breaks when many can be made part of paragraph style text flow properties, vertical spacing with empty paragraphs, use of Default Paragraph Style instead of Body Text, absolutely no usage of character styles (not your fault: they don’t exist in M$ Word), spacing /alignment with spaces and tabs instead of defining specific tab stops or ad hoc paragraph styles (in one case of this, a table would have been the correct structure).
My opinion may be very harsh: your document is not semantically structured nor formatted to any standard. Damage cause by contact with M$ Word and later conversion (in multiple steps) to ODF prevents any easy repair. The best you can do is to create a new blank document and to paste your contents as unformatted text to avoid “pollution”. Then style your document.
A simple criterion to know if your document is “correctly” styles is: you should have no empty paragraph and there should be no sequence of multiple spaces or multiple tab characters (and worse: no mix of both).
If you don’t know what styles are, I recommend you read the Writer Guide for an introduction.