You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you for the day?

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

ASSISTANT: Sure, I am gleeful to help you with that. May I know your name please?

USER: Sure, my name is William Rodriguez.

ASSISTANT: Please wait for a while, let me check your previous reservation status.

USER: Ok, take your time.

ASSISTANT: Thank you for waiting.

USER: Ok.

ASSISTANT: William Rodriguez, there is no active reservation found under your name to do changes in that.

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

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