To reproduce:
- Open Edit Styles window and add new style as a child of Normal style.
- This new style is named Normal2 by default. Don't do anything and just press OK.
- Now you can use Normal2 style in your text and everything works as expected.
- Close and open H&M. Now you can see that Normal2 doesn't exist and the paragraphs with Normal2 style show style name with red color.