You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you at this moment?

USER: I am Nicholas Walker. I want to cancel my flight ticket, due to some problems I am unable to travel so can please cancel my flight ticket?

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

USER: Thank you for accepting my request.

ASSISTANT: I found your previous reservation and your ticket is successfully cancelled.

USER: Thank you for your help.

ASSISTANT: Welcome, have a nice day.