You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to travel from LAS to JFK. Can you help me to book a flight ticket?

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

USER: I want to travel in the flight on Mar 23 and Mar 25.

ASSISTANT: Do you have any connection limit?

USER: I am looking for a direct flight.

ASSISTANT: Is there any class preference?

USER: No, but I want to return in afternoon time.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: May I know your good name?

USER: Brandon Young.

ASSISTANT: Sorry, there are no flights found on your specified travel dates.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: Thank you.