You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: Ok, please help me by providing your name so that I can check your current status of your reservation.

USER: Sure, I am Lisa Lee.

ASSISTANT: Wait a moment, let me check.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found under your name to change it.

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

ASSISTANT: Thanks for approaching us, have a nice day.