You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I best serve you today?

USER: I would like you to make my flight reservation from PHX to DCA, can you please help me?

ASSISTANT: When would you like me to book a ticket?

USER: Sure, I will depart on June 21st and return back on June 23rd.

ASSISTANT: May I know your name?

USER: My name is Jennifer Lewis.

ASSISTANT: Is there any other specifications regarding your journey?

USER: Please make sure that my depart and return time should be in the afternoon.

ASSISTANT: OK, please wait a moment.

USER: Sure.

ASSISTANT: Sorry Jennifer Lewis, we haven't found any flights based on your specifications.

USER: Sad to hear that. Anyway, thank you for checking.

ASSISTANT: Thanks for contacting us.