You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Charles Collins. I am planning to cancel an existing reservation, due to health issue. Can you please cancel my ticket?

ASSISTANT: I will help you with that.

USER: Thank you.

ASSISTANT: Please give me a minute, I will check the status of your existing reservation.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name in our database.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you for contacting us, have a nice day.