You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Kevin Lee here.

ASSISTANT: How may I assist you?

USER: My meeting got postponed as of now, so I need to change my existing reservation.

ASSISTANT: Kevin Lee, I am glad to help you with your concern. May I know your name to check with the reservation status? Please wait a moment.

USER: Ok.

ASSISTANT: Thank you for waiting. Kevin Lee, regret to inform that there is no active reservation found under your name to amend.

USER: That's ok, thank you.

ASSISTANT: Thank you for reaching us.