You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I had done a reservation last month but, it got postponed accidentally. Can you change my existing reservation?

ASSISTANT: Sure, may I know your name please?

USER: I am George Perez.

ASSISTANT: George, please wait for a moment. Sorry to inform you, there is no reservation found under your name.

USER: That's fine.Thanks for the information.

ASSISTANT: Thank you for contacting us.