You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Raymond Lee.

ASSISTANT: How may I assist you today?

USER: I have to buy some book in a whole sale market which is in Las Vegas, so can you reserve a flight ticket which will return back in the evening time?

ASSISTANT: I am oblige to help you with that. Can you please provide your preferable dates of travelling?

USER: Thank you and I want to take off on 21 Jan and I will recur back on 23 Jan.

ASSISTANT: Can I know your regional airports for booking?

USER: My nearest location airport codes are from EWR to LAS.

ASSISTANT: Do you have any class preference?

USER: No, I can travel in any flight.

ASSISTANT: Any connection limit do you have?

USER: I need a connection preference of 1.

ASSISTANT: Please be on hold to check the flights.

USER: Sure.

ASSISTANT: We are apologize that, there are no flights running towards your region with your requested dates of travelling.

USER: Sad to hear that one, I can ask my friend to help me out. Thank you for your service.

ASSISTANT: Thank you for reaching us, have a great day.