Writer heading restart after re-opening a document

System: LibreOffice 6.0, Win 10 x64, Laprop Acer 5738G. Document is saved as .odt

Problem in Writer Headings. When I apply a header everything is fine up until I close the document and re-open it. When in a session I apply headings, going to Paragraph ->Outline & Numbering. Numberign Style shows “Outline Numbering”. But after re-opening a document that style changes to “WWNum2”. This change causes problems with numbering order, since after re-opening of a document a new Heading applied starts from begining (Numerign style shows “Outline Numbering”).

It is possible to fix it by changing heading (e.g. from “Heading 2” to “Heading 1” and back to “Heading 2” ), but then I need to do it for all headings after each re-opening, which is not convenient.

Also, after re-open a document, when go to Paragraph ->Outline & Numbering in Numerign Style “Outline Numbering” is gone. so it can`t be selected.

Some pics:

Hopefully it is clear what I wanted to say. Can Anyone help?

The mere presence of WWNum2 indicates you saved as .doc or .docx. Does the glitch persist if you save as .odt?