Why I can not chnage the referencing style?

AW.Yapa

I wrote a manuscript with Harvard referencing style. However, now I have to change it to another style. When I change this though "Document preference > Manage Style; only change one citation.
This document has gone through multiple editions through different authors. However I am the only person edited (add/delete the references)
How can I fix this?

damnation

That sounds like you flattened your citations and that they're not active fields anymore.
See this guide for probable causes for this to happen and how to avoid it going forward: https://www.zotero.org/support/kb/existing_citations_not_detected

Do you have maybe an older copy of the document that still has the citations?

AW.Yapa

Thank you. It seems like that, unfortunately. I will add them to a new document. Because this document has gone through many editions through multiple authors.