You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Anna Green.

ASSISTANT: How can I assist you?

USER: Can you please help me in booking a ticket from AUS to OAK?

ASSISTANT: Sure, I will help you. May I know your depart and arrival dates?

USER: My preferred journey dates are June 22 and June 24.

ASSISTANT: In which class would you like me to book your flight ticket?

USER: I am comfortable with any class.

ASSISTANT: Do you prefer a stopover in between your journey?

USER: Yes, i require single stopover in between my journey.

ASSISTANT: At what time you are planning to depart and arrive?

USER: I would like to depart in the evening.

ASSISTANT: Give me a minute, I will check and let you know the flight availability.

USER: Sure.

ASSISTANT: Thank you for your time.

USER: Ok.

ASSISTANT: Unfortunately, there were no flights found that matches your requirements.

USER: It's ok, thank you for your response.

ASSISTANT: Thank you for approaching us.