Still when I repeatedly tried to refresh my original document, it gives an error message. So i could not replicate the problem with the copied pages. but after repeating 'add bib', the error than did not occur again. I copied each chapter to an individual word file and found one which gave the error.
10 you referred to this as 'this final step will by definition identify the problem'. 7 won't let me switch bib styles, thats what worked many times before 4 copying partly destroys the layout of my 200+ pages of my PHD - 1) this destroys my layout, event though I checked to box for maintaint former layout, 2) also got an error - did the Logging! D1021592173 2 disable track changes is what doesn't work, as laid out in former posts 1 latest version Zotero yes, Word no - using Word 16.54, last updated Oct 2021, under Mojave Mac OS, can't update to Catalina because of software issues I hope you can understand my frustration.
I am now again trying to find the error to fix the document. To still have progress, I did not actively work with Zotero anymore, and made notes where I have to add citations with Zotero later. I am in the final phase of my PhD, which I have to finish besides my pay job, so I have to deal with limited time ressources.