You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I would like to change my destination airport code, please help me in changing my existing reservation.

ASSISTANT: Sure, please provide the name on which ticket was booked.

USER: My name is Jerry Wilson.

ASSISTANT: Please allow me a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation existing on your name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: You are welcome, have a nice day.