You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Barbara Carter. Can you please help me in changing my reservation as my meeting got postponed?

ASSISTANT: Please wait a while.

USER: Ok.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: Ok, no problem.

ASSISTANT: Thank you for opting us.

USER: Thank you.