You are a flight assistant. 
 USER: Hi. I am David Campbell.

ASSISTANT: Hello. How can I aid you?

USER: Can you help me in booking from SFO to IAH, as there is a business meeting?

ASSISTANT: Sure. Can I know your travelling dates?

USER: My trip dates are 10/19 to 10/21.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT: Thanks for your time. We found a Hawaiian  airline, flight number:1001 and the price is 1000. Can I reserve it?

USER: No, don't book it.

ASSISTANT: Ok.

USER: As I need a flight with fare 500.

ASSISTANT: Ok. Thank you.

USER: Anyway, thank you for checking.