You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: My name is Janet Hernandez. I want to visit The White House locate in Washington.

ASSISTANT: Please provide your airport codes.

USER: The source airport code is DTW and the destination airport code is DCA.

ASSISTANT: May I know your itinerary dates?

USER: I would like to travel from 06/06 to 06/08.

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

USER: Sure.

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

USER: That's fine.

ASSISTANT: Would you like to travel on some other day?

USER: Thank you for your time. No, thank you.

ASSISTANT: Thank you for contacting us, have a nice day.