You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you for today?

USER: Due to heavy snowfall in my location, I want to change my existing reservation.

ASSISTANT: Yes, I can help you. Can I know your name for further proceedings?

USER: Sure, my name is Andrew Hall.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: Ok, thank you for your response.

ASSISTANT: Thank you for approaching us.