You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

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

ASSISTANT: Sure, may I know your name?

USER: My name is Christopher Gonzalez.

ASSISTANT: Please wait a moment.

USER: Ok.

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

USER: Thanks.

ASSISTANT: Thank you for choosing us.