You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

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

ASSISTANT: Sure, I am glad to help you with that. Can I know your name to check your previous reservation?

USER: Richard Baker here.

ASSISTANT: Please wait a moment to check.

USER: Ok.

ASSISTANT: We regret to inform you that, there is no reservation found on your name in our records.

USER: Thank you for the help.

ASSISTANT: Thank you for approaching us, hope you have a great day.