You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: Daniel Nelson here. I planned to meet my friends.But suddenly, I have urgent meeting.So I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, we are here to help you. We didn't found any reservation by this name.

USER: Any way, thank you for the information.

ASSISTANT: Thank you for consulting us.