You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you aid me to change my reservation due to an emergency?

ASSISTANT: Sure, I am glad to help you.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Samuel Lopez here.

ASSISTANT: Ok, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry to say that, no reservation was found on your name to change.

USER: Thank you for the help.

ASSISTANT: Thank you for choosing us.