You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I serve you today?

USER: I want to change my existing reservation owing to an emergency.

ASSISTANT: Sure, I will help you  with that. May I know your name to proceed further?

USER: My name is Brian Moore.

ASSISTANT: Please wait for a while.

USER: Sure.

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

USER: Thank you.