Styles reassigning in documents

[ryannah05]

I think I'm going crazy! I'm using templates with a lot of custom styles, which work great 98% of the time. Periodically I get a really strange and very annoying issue -- most of the styles suddenly reassign themselves. For instance, everything that used to be "Figure_Title" style is suddenly "TOC 2," everything that was "Figure" is suddenly "Bullet_DS," everything that was "Footnote Text" becomes "Heading 4," etc. Undo doesn't fix the style changes, but if I immediately exit without saving and then reopen, the file is correct. It seems to be random as to which document it will strike, but when it does happen, it's almost always when I open the header/footer or start editing a table. Has anyone else seen this? Any idea what could be causing it or what I might need to change in the template, styles, or whatever else to keep it from happening? I'm using Word 2016.

[Stefan Blom]

In Word, click File > Options > Proofing > AutoCorrect Options > AutoFormat As You Type. Clear the check mark next to "Define styles based on your formatting." (The words are misleading, because the option actually means "apply styles.")

[ryannah05]

Thanks for the response. "Define styles based on your formatting" is already unchecked in the template.

[Stefan Blom]

Thanks for the follow-up.

When it occurs, can you always fix the issue by closing and re-opening the document?