You are a flight assistant. 
 USER: Hi. I am Nicholas Hall.

ASSISTANT: Hello, how may I aid you at this moment?

USER: I am looking for a flight from Washington, can you help me in booking the flight ticket from DCA to PHX?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: My travel dates are from Mar 15th till Mar 17th.

ASSISTANT: Do you have any limitations?

USER: I need a flight with 1 stop over or direct flight to reach my destination  soon.

ASSISTANT: Sorry, there is no flight available on your travelling dates.

USER: That's ok, not an issue. Thank you for your help.

ASSISTANT: You are welcome, have a nice day.