You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

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

ASSISTANT: Sure. Please let me know your travelling dates.

USER: I will start on Dec, 31 and return on Jan, 2.

ASSISTANT: Is there any airline preference?

USER: No.

ASSISTANT: Do you have any preferences?

USER: I would prefer single connection.

ASSISTANT: Found ticket with United airlines for price 200. Shall I book a ticket?

USER: Yes, please book.

ASSISTANT: Can I know your name?

USER: Helen Campbell.

ASSISTANT: Your ticket is booked having flight number 1004.

USER: Thank you.

ASSISTANT: Thanks. Have a nice day!.