You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I provide assistance to you?

USER: I want to travel from HOU to AUS. Can you help me to book a flight ticket?

ASSISTANT: Sure, may I know your trip dates?

USER: I want to fly in the flight on June 23 and June 25.

ASSISTANT: Do you need any break in your journey?

USER: I am looking fora direct flight.

ASSISTANT: May I know your depart and arrival time?

USER: I don't have any.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: Sorry to inform you that, there are no flights available with your requirements.

USER: That's ok. Anyways, thank you.

ASSISTANT: For references, may I know your name please?

USER: Stephen Smith.

ASSISTANT: Thank you for choosing us.