You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to go Washington in this winter holiday for visiting National Gallery of Art, can you please help me in booking flight ticket from Las Vegas?

ASSISTANT: Sure, could you please share your preferable travel dates?

USER: I would like to departure on 12/12 and my return date is 12/14.

ASSISTANT: Can you please provide the airport codes?

USER: I want to take off from LAS and destination airport is DCA.

ASSISTANT: May I know your name to proceed further?

USER: Sure, my name is Jonathan Lee.

ASSISTANT: Jonathan, there is a flight available with price 200 and the connection limit is 0 with UA airlines. Would you like me to proceed the booking?

USER: But I want 1 connection limit, so please don't book this flight ticket.

ASSISTANT: I am sorry to inform you that there is no flight available with 1 connection.

USER: It's ok no problem, I will go with another airline. Thank you for your information.

ASSISTANT: You are welcome. Thank you for contacting us.