You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you help me to book a flight ticket from JFK to IAD?

ASSISTANT: Can I have your journey dates?

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

ASSISTANT: Do you need any connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other specifications?

USER: I prefer to depart in the evening.

ASSISTANT: May I know your name?

USER: I am Katherine Scott.

ASSISTANT: There are no flights available on your routes.

USER: It's ok, not a problem, thank you.

ASSISTANT: Thank you for opting us.