I asked the AI to rewrite my chapter and it says "the rewrite came back cut off or the wrong length, so the chapter was left as it was". What happened?

From version 1.9.21, BookyAI checks every rewrite of your own chapters before keeping it. Each kind of rewrite has a sensible length: "Polish" and "In the book's style" stay close to your length, "Expand" must come back longer and "Tighten" shorter. If the AI's answer was cut off, padded, summarised or far from that length, BookyAI does not keep it: your chapter stays exactly as it was and nothing is marked. Simply try again, or try another AI engine. Very long chapters are the most likely to come back cut off on small or free models.