You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, How can I aid you?

USER: Please change my existing reservation as my trip dates of are postpone.

ASSISTANT: Sure.

USER: Thank you.

ASSISTANT: May I know your good name?

USER: Reservation is done with my name Kathleen Roberts.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Thanks for waiting. There is no reservation found on your name.

USER: Ok, thank you for information.

ASSISTANT: Thanks for choosing us.