You will hear a conversation between a manager and an employee management consul

Woman: Hello, Tim. Something wrong? What can I do for you?
Man: Well. I do have a problem. I have an employee whose responsibilities include both reception and office administration work, and also data entry of our sales leads.
Woman: And?
Man: In recent months her attitude has become problematic, so much so that other employees are afraid to approach her about tasks and duties. At times she seems almost unwilling to do even the most obvious tasks that an office admin should perform like express packages and such. l have difficulty addressing this problem because it happens randomly—sometimes she has a great attitude and is very eager to complete tasks, other times she seems annoyed or frustrated that we even dare not ask her to do something. The word "moody" comes to mind. I know she thinks this job is " beneath her" and that she is looking for something more. But how can I give her more when she has demonstrated such poor behaviour?
Woman: I see. I believe your admin’s " moodiness" is passive aggressive behaviour.
Man: What does that mean?
Woman: That is, she is unhappy with something in her life and expressing that unhappiness in her work behaviour. Unhappiness with what? I cannot venture to guess. Only she knows the answer. Consequently, the best way to deal with these situations is to confront the behaviour.
Man: Then, what am I supposed to do?
Woman: I suggest you meet with her privately to give her your observations. Then, ask her what she thinks is the reason for her unprofessional behaviour. If she is honest, she will take this opportunity to tell you what the real issue is and give you the opportunity to help her solve the problem. If she is hiding something, I mean dishonest, she will make an excuse that makes no logical sense to you.
Man: What if the latter happens?
Woman: You need to explain to her that her moodiness is unacceptable behaviour for a professional and that she must change it immediately and respond positively to her co-workers from this time forward. Advise her that you are documenting this conversation in an email to her and to Human Resources. And, that you will indicate in this email a date for a follow-up meeting with her in 2 weeks to give her your feedback on whether she is performing professionally as per your directive.
Man: So what should I do when this date arrives?
Woman: You must be prepared for either positive news, and a pat on the back for her improvement, or bad news that her position is terminated. If the news is good, then you might discuss with her what she is looking for in her next career move so that she knows you are thinking about her future.
Don’t make any commitments at this time. You want to see whether the new improved admin continues her positive performance for several months before you discuss a new role for her. If you must terminate her, be sure you have a succession plan to replace her and be sure that HR and Security are aware that she is leaving the company this day. Tim, I hope this response helps you resolve this challenge.
Man: I think it will. Thank you very much.