You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

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

ASSISTANT: Sure, please share me your trip dates.

USER: I prefer to travel on Dec 15 and Dec 17.

ASSISTANT: Do you need direct flight or connecting flight?

USER: I prefer to travel in a connecting flight.

ASSISTANT: For booking, we need your good name. Please mention it.

USER: I am Benjamin Clark.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for availing us.