You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Due to an emergency, I want to change my reservation. Can you help me?

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

USER: Daniel Anderson here.

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

USER: No problem, Thanks for the information.

ASSISTANT: Thank you for reaching us.