Sometimes, you will see citations like “(J. Smith 2000, J. R. Smith 2001)”, even though your citation style normally only shows the author's last name (“Doe 2004”). In these cases, Zotero is trying to disambiguate different authors. This is generally a good thing, but disambiguation also occurs when a certain author is inconsistently named in your Zotero library. For example, Zotero treats the names

• Jeff Smith
• J. Smith
• J. R. Smith

as distinct individuals. In this case, you can either go through your library and change all the names that refer to the same person to the exact same form, or you can simply use a style that doesn't disambiguate names. A step-by-step guide to disable given name disambiguation in a CSL citation style can be found here.

Zotero and CSL support sophisticated disambiguation rules. If a style disambiguates incorrectly, please post to the Zotero Forums and provide documentation in form of a style guide or a published article in the publication in question. Note that these changes do not address the issue of inconsistently named authors.

If you've made sure that the author's name is formatted consistently in Zotero, one or more of your items may be pointing to an item that you've deleted from Zotero. When this happens, Zotero uses metadata embedded in the document instead. To check whether an item is still linked to your Zotero library, click on the citation, click Add/Edit Citation, click the blue bubble in the citation dialog (red bar, not classic), and look for an “Open in [Library]” button at the bottom of the popup. If the button doesn't appear, the citation is no longer linked to Zotero, and you will need to delete the citation and reinsert it, being sure to select from the appropriate library in the citation dialog search results.

If you have more than one copy of an item and cite both in separate places, Zotero will treat the authors as separate and disambiguate them in the text. You can fix this by merging the items in Zotero, either via the Duplicate Items view or by selecting the items in the main items list, right-clicking, and choosing “Merge Items…”, and then clicking the plugin's Refresh button.

If you're seeing citations with dashed underlines, you've disabled Automatic Citation Updates. You can either press Refresh to update citations manually or re-enable Automatic Citation Updates in the plugin's document preferences.