You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you?

USER: Please change my existing reservation owing to an emergency.

ASSISTANT: Sure, we are here to help you. May I know your good name to proceed further?

USER: I am Mark Carter.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Thanks.

ASSISTANT: Thank you for opting us.