You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,. How may I serve you?

USER: I am Mary Wilson. My business meeting got postponed, so I want to change an existing reservation. Could you help me in changing the reservation?

ASSISTANT: Sure, I am here to help you. Please standby, I will get back to you.

USER: Sure.

ASSISTANT: Sorry, we do not found any reservation on your name to change your reservation.

USER: Not an issue.

ASSISTANT: Thanks for approaching us, hope to serve you again.

USER: Thank you for your quick response.