You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I would like to book a flight ticket from DEN to CLT.

ASSISTANT: Sure, can I know your preferable dates?

USER: My preferable dates are from 03/27 to 03/29.

ASSISTANT: I am sorry to inform you that there are no flights. Can I know your name?

USER: My name is Thomas Phillips.

ASSISTANT: Thank you.

USER: Thank you for your time.