You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What can I do for you at this moment?

USER: I am William Miller, I planned a trip to Charlotte but I have to cancel my trip due to my bad heath.

ASSISTANT: Ok.

USER: Can you cancel the ticket?

ASSISTANT: Sure. Give a minute, I will check the status of your previous reservation.

USER: Sure.

ASSISTANT: Thanks for being patience. We found that there was no reservation existed with your name.

USER: Ok, thanks for the information.

ASSISTANT: Thank you for opting us.