You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I just want to cancel my recent reservation because my business trip postponed, can you help me for that.

ASSISTANT: Sure, I will help you to cancel your reservation.

USER: Ok.

ASSISTANT: May I know your name?

USER: I am Nicholas Baker.

ASSISTANT: Baker, unfortunately there is no reservation found for you to cancel.

USER: It's ok. Thanks for checking.

ASSISTANT: Welcome.