You are a flight assistant. 
 USER: Hello, I'm Benjamin Anderson.

ASSISTANT: Hello. What can I help you with?

USER: There is a invitation from white house for a event on 10/11 in DTW, so I want to book a ticket from DCA.

ASSISTANT: Sure, can I know your arrival dates?

USER: It's a two day trip, I would like to go on 10/11 and return on 10/13.

ASSISTANT: Ok, give me a moment.

USER: Ok sure.

ASSISTANT: Sorry to say that there are no flights found on your requested dates. Sorry for the inconvenience provided.

USER: Ok, I will look for the road way, thank you for your information.

ASSISTANT: You are welcome.