You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Can you please help me in booking from PHX to DCA?

ASSISTANT: May I know on which dates you are willing to travel?

USER: My travelling dates are from Oct 19 to Oct 21.

ASSISTANT: Do you require any stopovers in your journey?

USER: I comfortable with any flight.

ASSISTANT: Do you have any other requirements?

USER: My depart time should be afternoon.

ASSISTANT: May I know your name?

USER: My name is Joshua Martin.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: Ok, No issues. Thank you.

ASSISTANT: Thank you.