I'm sure I once read somewhere (pre-Internet) the in-story explanation that Janice-as-Kirk got Angela's name wrong when calling her Lisa, but Angela didn't want to correct the Captain. I don't think it was in Blish... racking my brain to remember what book that was in.
It wasn't Blish; the adaptation puts Uhura in the place of "Lieutenant Lisa."
The Star Trek Concordance lists Baldavin's character as "Angela" and says that Lester-as-Kirk calls her Lisa by mistake, which is probably what you're thinking of. But Trimble gave "Angela" a separate entry from Angela Martine, apparently considering them different characters. That's weird. The character was officially billed simply as "Communications Officer," and is never called "Angela" at any point in the episode. Maybe Trimble saw some behind-the-scenes memo from someone suggesting that the character should be called Angela, but didn't realize why the suggestion was made.