You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I would like to visit the Great Museum at New York. Can you help me in booking a ticket?

ASSISTANT: Sure, I will help you out. May I know your travelling dates please?

USER: I would like to travel on 10/18 and return on 10/20.

ASSISTANT: Can I know your airport codes too?

USER: The respective airport codes are ATL and LGA.

ASSISTANT: May I know your name please?

USER: My name is Christopher Walker.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there are no flights found.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.