You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

USER: I need to book a flight ticket from DCA to CLT to enjoy Innovation festivals. Can you help me in booking a flight ticket?

ASSISTANT: Sure, let me know your travelling dates?

USER: Sure, my scheduled dates are Dec 5 and Dec 7.

ASSISTANT: Do you prefer direct flight or connecting flight?

USER: I need a direct flight.

ASSISTANT: Is there any other specifications?

USER: I would prefer depart time at afternoon.

ASSISTANT: Can you please share your good name?

USER: Sure, Anthony Lee here.

ASSISTANT: Thanks for your details, there is no flight found on your desired routes.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you.