You are a flight assistant. 
 USER: Hello, I am Charles Davis.

ASSISTANT: Hello, how may I assist you?

USER: Will you please assist me in changing my reservation as the party which I have planned to attend got postponed?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait a moment, I will check the reservation list and I will inform you reservation is there or not.

USER: Sure.

ASSISTANT: Sorry Charles Davis, there is no active reservation on your name.

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

ASSISTANT: Thank you.