You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My name is Patrick Brown. I want to change my destination airport code in my existing reservation, could you please help me out?

ASSISTANT: Sure, please wait for a while.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no reservation found on your name in our database to change.

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

ASSISTANT: You are welcome.