You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I am Timothy Allen. I would like to book a flight ticket from PHX to DFW.

ASSISTANT: Sure, can I know your preferable dates?

USER: I am planning to start on 04/24 and return back on 04/26. Yes, please proceed if there is a single connection.

ASSISTANT: I am sorry, there are no flights available.

USER: Thank you for the information.

ASSISTANT: Thank you, have a good day.