You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: Please book a flight ticket to DCA from PHX to meet my cousin.

ASSISTANT: Sure, may I know your travelling dates?

USER: My travelling dates are on May 23 and 25.

ASSISTANT: Ok, could I have your name please?

USER: Sure, my name is Donald Lopez.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a connected flight.

ASSISTANT: Sorry, there is no flight with your requests.

USER: That's Ok, I will choose another alternative to go. Thank you.

ASSISTANT: You are welcome, have a great day.