Since I realized this wasn't specified anywhere else, I thougth now would be a good time to explain it further. The Isolation Cell is a part of the game. A lot like the "skip a turn" thing in other board games. Your character will most likely be thrown in there if she breaks any of the basic rules that the guards have explained in the Beginning Topic. The duration will vary depending on the severity.
While you are in isolation, you can NOT roleplay outside of it, and will have to wait out the time. You can also be thrown into isolation by request if you're going away for a week or something. It would help explain your inactivity.
Don't worry, the isolation will never last long, most commonly only a week, and you'll be back to playing in no time!