You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you today?

USER: I made a reservation earlier to attend for a meeting, but it has been postponed.

ASSISTANT: Ok.

USER: Can you please change my existing reservation?

ASSISTANT: Sure, may I know your name?

USER: Sure, I am Raymond Allen.

ASSISTANT: Ok, please wait a moment.

USER: Sure, I will wait.

ASSISTANT: Thanks for your precious time, there is no active reservation found on your name.

USER: Ok, Thank you for providing information.

ASSISTANT: Thank you.