You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I am Jeffrey Parker. I would like to book a flight ticket from LAX to HOU. Could you please help me up?

ASSISTANT: Sure, can I know your preferable dates?

USER: After a long thinking, I have decided to board the flight on 08/17 and fly back on 08/19.

ASSISTANT: I am sorry, there are no flights available. Thank you, have a good day.

USER: Ok. Thank you for the information.