You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I address you?

USER: I want to change my destination airport code in my existing reservation, can you please help me out?

ASSISTANT: Sure. May I know your name?

USER: Sure, my name is Raymond Jackson.

ASSISTANT: We found a reservation by this name. Can you let me know your update journey dates?

USER: Sure, my planned travelling dates are May 07 and May 09.

ASSISTANT: Where would you like to travel?

USER: Sure, I would like to travel from MCO to CLT.

ASSISTANT: Do you have any other requirements?

USER: Yes, my return time must be in afternoon.

ASSISTANT: Ok.

USER: I prefer economy class.

ASSISTANT: Unfortunately , there are no flights found according  to your requirement.

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for choosing us.