Q: What should I do if a reviewer removed my name as a coauthor during the revision stage?

Answer: As with all coauthorship conflicts, there are several aspects to this issue. So, let’s take them one by one.

• Reviewer action: Firstly, if your understanding is correct (that the reviewer had your name removed), this is an unusual scenario. Most coauthorship disputes arise from the first author removing or adding the name of a coauthor. A reviewer adding or removing a coauthor name is less common, although it does happen, as you can read in this query by another researcher. Also, while your guess about this reviewer’s background and intentions (that it is someone with whom you have previously encountered issues) may be accurate, we shall perforce have to keep it out of this discussion as that is not clearly established.
• Journal response: The journal editor is supposed to communicate only with the corresponding author. From what you have described, you may not be the designated corresponding author, and so, the editor may not have responded to your mails so far. Also, for any (co)authorship conflict, the journal usually needs the authors to mutually resolve the conflict. What the journal needs from the authors is a signed form about the (co)authorship details or changes, mentioning the first author, the coauthors, and the corresponding author (or changes to these, as applicable)
• First author contact: You have mentioned that the first author has not contacted you about the name removal. It may be an oversight on their part, a misunderstanding, or in the worst case, actually intentional. From what you have described, it seems the two of you are not in touch in person but only remotely. To resolve this issue, from what we understand so far, the first and best way would be to get in touch with the first author. You can share the information with them, come to know their understanding of the situation, and then decide the best way to proceed. You haven’t mentioned the nature of your relationship with the first author, but if they are reasonable, they are likely to strive to address the issue.
• Other actions: In case the first author is not cooperative, there are various other measures you can adopt. These also depend on the exact stage of publication at which your paper is. Some of the measures include contacting the journal’s editorial board and the Committee on Publication Ethics (COPE). You may get some understanding of these actions in this other query: How should a journal address an authorship dispute?

All the best for a satisfactory resolution!

You may also find these other resources insightful:

• Foul play in scientific publishing: The phenomenon of academic papers being held hostage
• The final manuscript should be approved by the co-authors before submission [Case study]
• How to avoid retractions and publish ethically [Course]