You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may 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 am here to help you out. May I know your travelling dates please?

USER: Can you please check with my name?

ASSISTANT: Sure, may I know your name please?

USER: Sure, my name is Shirley Hill.

ASSISTANT: Shirley Hill, we haven't found any reservation under your name in our database.

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

ASSISTANT: Thank you for choosing us.