You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: I planned to meet my friend in SFO, can you please help me to book a flight ticket from DCA?

ASSISTANT: When you are willing to travel?

USER: I prefer to travel on Feb 24 and Feb 26.

ASSISTANT: Do you have any connection limit?

USER: I prefer to travel in a connecting flight.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: May, I know your good name?

USER: I am Carol Moore.

ASSISTANT: Sorry, we found no flights on your given dates.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your information.