You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation, my music concert got postponed. Can you please help me out with that?

ASSISTANT: Sure, I am glad to help you.

USER: Thank you for your positive response.

ASSISTANT: May I know your good name to proceed further?

USER: Sure, my name is Joshua Baker.

ASSISTANT: Please be on hold.

USER: Ok.

ASSISTANT: There is no active reservation found on your name in our database to change it.

USER: That's ok, no problem.

ASSISTANT: Thank you for availing us.

USER: Thank you for your information.