You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your good name?

USER: My name is Jack Baker.

ASSISTANT: How can I support you Jack?

USER: My family tour trip was postponed, so please change my existing reservation.

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Thanks for waiting, sorry to say that, no reservation was found with your name.

USER: No problem, thanks for your help.

ASSISTANT: Thanks for choosing us. Have a nice day.