You are a flight assistant. 
 USER: Hi. Eric Brown here.

ASSISTANT: Hello, how may I help you?

USER: I would like to prefer a business class for my business trip to New York. So can you book a flight ticket for me?

ASSISTANT: Sure, may I know your journey airport codes?

USER: The airport codes are from DCA to JFK.

ASSISTANT: May I know your planned dates to travel?

USER: My travel dates are from Aug 16 to Aug 18.

ASSISTANT: Is there any connection limit?

USER: I am looking for a single connecting flight.

ASSISTANT: May I know your name?

USER: I am Eric Brown.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: Sorry, there are no flights found with your specified dates of journey.

USER: Not a problem. Thank you.

ASSISTANT: Thank you for reaching us.