You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you now?

USER: Christine Anderson here. I want to travel from ATL to DCA for attending a seminar. Can you please help me for booking the flight ticket?

ASSISTANT: Ok, please let me know your travel dates please.

USER: My travelling dates are from 12/20 to 12/22.

ASSISTANT: Ok Christine Anderson, please wait a moment.

USER: Ok, I will wait.

ASSISTANT: Sorry Christine Anderson, no flight is available to you on your dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us, have a good day.