You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Dorothy Smith.

ASSISTANT: Smith, how may I help you?

USER: Can you assist me in booking my flight ticket from Washington DC-IAD to DC-DCA.

ASSISTANT: Sure, I am here to help you. Please share your itinerary dates.

USER: 02/01 to 02/03 will be my travelling dates.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no flight is available on your route.

USER: Ok, thank you.

ASSISTANT: Thank you for choosing us.