You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Matthew Adams.

ASSISTANT: What service that you are looking from our agency?

USER: I want to change my destination airport code in my existing reservation, could you mind help me in changing?

ASSISTANT: Sure, I am glad to help you with that.

USER: Thank you.

ASSISTANT: Please wait a moment to check your previous reservation.

USER: Ok, take your time.

ASSISTANT: When I have checked our database, It shows no reservation on your name.

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

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