I Want a Steady Employment

So my friend applied for a job via posting!!!! However once she transferred departments a month later they changed the job description entirely and now she feels obligated (but does not want) to stay. I’m really upset because it seems so deceptive. They gave ZERO indication that this would be happening. I told her just as they lied to her she can pick one aspect of the job she is unwilling to do and simply bow out of the job