When you repaired it, did you change the in-game prompt at all? The in-game System Prompt field must have "with no line breaks or indentations" in it.
Alternatively, you can try specifying it further. Try adding the following to the in-game prompt:
- game_text cannot include line breaks, "/r" or "/n"
Edit: If you are okay with it, can you post the system prompt that you are using? I could try using that to figure out why the AI is acting like this. Normally a new line should be "\n", not "/n". The slash is the other way around.