You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I amend you today?

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

ASSISTANT: Sure, please wait for few minutes.

USER: Ok.

ASSISTANT: May I know your name please?

USER: I'm Stephen Jones.

ASSISTANT: Thank you for waiting.Sorry we couldn't find any reservation with your name.

USER: Thanks.