You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my existing reservation, due to postpone of my examination. Can you help me out?

ASSISTANT: Sure, please help me with your name to check your previous reservation.

USER: Myself Carol Hill.

ASSISTANT: Thanks for your name, please hold on.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name.

USER: Ok, not an issue. Thank you for your kind information.

ASSISTANT: Thank you.