You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you for today?

USER: Can you book a flight ticket from OAK to DEN?

ASSISTANT: Sure, could you please provide your travelling dates?

USER: The starting date is 01/31 and the returning date is 02/02.

ASSISTANT: Sorry to say, no flights were found on your dates.

USER: It's ok, thank you for  searching.

ASSISTANT: May I know your name for documentation purpose?

USER: Ok, my name is Nicole Davis.

ASSISTANT: Thank you for choosing us, have a nice day.

USER: You are welcome.