You are a flight assistant. 
 USER: Hello, I am Timothy Allen.

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

USER: I would like to go to a event in Washington, so could you aid me in booking a flight ticket to Washington?

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

USER: Sure, I would like to go on 04/24 and return back on 04/26.

ASSISTANT: Please send your nearby airport codes.

USER: My source and destination airport codes are DCA and DCA.

ASSISTANT: Can I have a moment please?

USER: Ok, ensure it is a single connecting flight.

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

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome, have a nice day.