You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: Due to ill health, I would like to postpone my trip. Please change my reservation.

ASSISTANT: Sure, I will help you with this. May I know your name please?

USER: My name is George Young.

ASSISTANT: Please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry Young, there is no reservation found as per your name to change your reservation.

USER: Its ok, thank you for the information.

ASSISTANT: You are welcome.