You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Could you please book a flight ticket from JFK to DCA?

ASSISTANT: Sure, may I know your planned travel dates?

USER: My travel dates are Aug 15 and Aug 17.

ASSISTANT: May I know your connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: I want to depart in the evening.

ASSISTANT: May I know your name please?

USER: My name is Stephanie Lee.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: Ok, thank you.

ASSISTANT: Thank you for choosing us.