You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I would like to change my existing reservation, due to postpone of my business meeting. Can you please assist me in changing?

ASSISTANT: May I know your name?

USER: James Roberts.

ASSISTANT: Sorry, we did not found any reservations under your name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for reaching us.