You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you today?

USER: I am planning to postpone my trip to next week so, can you please change my existing reservation?

ASSISTANT: Ok, I can help you easily.

USER: Thank you.

ASSISTANT: May I know your name?

USER: Timothy Mitchell is my name.

ASSISTANT: Please wait for a couple of minutes.

USER: Sure.

ASSISTANT: Sorry Timothy Mitchell, no reservation found on your name in our reservation list.

USER: Ok, that's not a problem. Anyhow thanks for the information.

ASSISTANT: Thank you for approaching us, have a nice day.