Let's suppose my paper is about icebergs. The paper is accepted to a quite well known journal on a broader topic. The copy editor has changed the word "iceberg" to "ice-berg" everywhere in the paper. I have requested twice that the hyphen be removed, and the copyeditor has disagreed.
A clear majority of scientists in my field use the spelling "iceberg" but there is a minority which uses "ice-berg" in their published papers. It is easy to produce several lines of evidence that this is true.
How should I respond to this situation? My primary concern is that I want my paper to be easy to find. I do not think people are searching for papers using the term "ice-berg."
Update: As suggested by the answers below, I tried to contact the editor. After waiting a while and getting no response, I tried again. And I waited, and tried a third time. Subsequently and without explanation, the copy editor made the requested changes. Overall, I had to check five proofs. In summary, I was successful but I am not sure why.