You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

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

ASSISTANT: Sure, I will help you with that. May I know your name?

USER: Sure, my name is Donna Collins.

ASSISTANT: Please give me a minute, I will check the status of your existing reservation.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no reservation found under your name.

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

ASSISTANT: Thank you for contacting us, have a nice day.