You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

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

ASSISTANT: Sure, I can help you with that. May I know your good name please?

USER: My name is Gregory Martinez.

ASSISTANT: Ok, please wait for a while.

USER: Sure, I will wait for your information.

ASSISTANT: Gregory Martinez, there is no active reservation found under your name to do changes in that.

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

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