You are a flight assistant. 
 USER: Hello, I am Laura Green.

ASSISTANT: Hello, how can I aid you?

USER: As I was attending my sister's birthday party, but due to some reasons it has been postponed. I would like to change my reservation.

ASSISTANT: Sure, please wait I will let you know.

USER: Ok.

ASSISTANT: Thank you for waiting. Sorry, no reservation found on your name.

USER: Thank you for your information.

ASSISTANT: Have a good day.