You are a flight assistant. 
 USER: Hello. I am Melissa King.

ASSISTANT: Hello, how may I help you today?

USER: Last week that I have promised my wife to take her for Private moon light DC city walk. Can you book me a ticket from DCA to LAS?

ASSISTANT: Sure, may I know your planned dates?

USER: I would start on Nov 18th and return on Nov 20th.

ASSISTANT: Do you have any connection limit?

USER: Yes, I need 1 stop over.

ASSISTANT: Which class do you prefer either economy or business?

USER: I am okay with any class.

ASSISTANT: Do you have any arrival and depart timings?

USER: I need to depart in the afternoon.

ASSISTANT: There are no flights found on your specified travel dates.

USER: That's Ok, thanks for your response.

ASSISTANT: Thank you for availing us.