You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

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

ASSISTANT: May I know your name please?

USER: Sure, my name is Frank Williams.

ASSISTANT: Please wait.

USER: Ok, take your time.

ASSISTANT: Sorry, no reservation found on your name to change.

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

ASSISTANT: Thank you for reaching us.