You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I have to cancel my ticket booking due to some health problems, can you please cancel it?

ASSISTANT: Sure, I will help you with the flight ticket cancellation. May I have your name please?

USER: Sure, I have done my previous reservation on my name Richard Green.

ASSISTANT: Ok. I have searched online but I could not find your flight reservation to cancel it.

USER: Thank you for your help, that's not a problem.

ASSISTANT: Thank you.

USER: Welcome.