You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Ashley Harris.

ASSISTANT: Ashley, how can I assist you?

USER: I want to visit a historical place in Phoenix.Can you book a ticket from DC - DCA to AZ - PHX?

ASSISTANT: Sure, can you provide your travel dates?

USER: I want to depart on 08/04 and return by 08/06.

ASSISTANT: Let me check, please wait for a while.

USER: Sure.

ASSISTANT: Flight number 1025 of Spirit airlines is available for you.

USER: Ok, proceed with the booking.

ASSISTANT: Your ticket is booked.

USER: Thank you for your help.

ASSISTANT: Thank you for contacting us.