In a test that I just performed here, the difference between a document in which the "Automatically update document styles" box was checked and the same document where it was unchecked, was the presence in the former of the xml statement in the word\settings.xml
file of
<w:linkStyles/>
If I deleted that xml statement and then re-zipped the file and changed the extension back to .docx, it was possible to open the file without any error message appearing and on going to the Templates tab of the Templates and Add-ins dialog, the "Automatically
update document styles" box was unchecked
In another test, with a document in which the "Automatically update document styles" box was unchecked, if I added
<w:linkStyles/>
into the settings.xml file and then rezipped the file and changed the extension and opened that file, he "Automatically update document styles" box was checked.
I do not know why ChangSun23 was getting some kind of unknown data dependency loss, but it definitely appears that the presence or otherwise of
<w:linkStyles/>
is what controls the settings for "Automatically update document styles".