Not to defend Farrah
But if I remember correctly, (according to Farrah) Kiana was the one who called Farrah and asked if she could clean the machines. She claimed she knew what she was doing and Farrah finally gave in. Kiana soon realized she was in over her head and started blowing up Farrahs phone because she couldn't do it as well as she originally thought.
If that was really the case then I could see why Farrah had a reason to be frustrated. If I told an employee no and they kept pushing to do it and ended up with me having to do something I didn't want to do right then in the first place I'd be a little irritated too.