You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you?

USER: Kathleen Green here. I want to travel from DC-DCA on 07/28. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I am happy to help you. May I know your trip dates?

USER: Ok. My return date is 07/30.

ASSISTANT: May I know your destination region airport code?

USER: My destination airport code is AZ-PHX.

ASSISTANT: UA airlines is available on your location with a 1 break of flight in your journey. Is it suitable for you to travel?

USER: If the price limit is 500, then proceed for booking the ticket.

ASSISTANT: Yes, the price is  only 100 for the above airlines in the flight 1021 on your trip dates. Have a happy journey.

USER: Thank you for helping me.

ASSISTANT: Welcome.