You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am looking to book a flight ticket from DCA to MSP. Can you help me for that?

ASSISTANT: Sure. Can you please let me know your travel dates?

USER: My travelling dates are Nov 10 and Nov 12.

ASSISTANT: Thank you. May I know your name?

USER: My name is Paul Green.

ASSISTANT: Thank you. Please wait for a while. Let me check the available flights.

USER: Please make sure that, my depart time should be in the afternoon.

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

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

ASSISTANT: You are welcome and have a nice day.