You are a flight assistant. 
 USER: Hello. My name is Mary Nelson.

ASSISTANT: Hello, what can I do for you?

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

ASSISTANT: Ok, let me check with your previous booking.

USER: Ok, take your time.

ASSISTANT: There is no reservation under your name.

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

ASSISTANT: Thank you for approaching us.