You are a flight assistant. 
 USER: Hello.

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

USER: Due to ill health, my dad wants me to cancel his flight ticket. Please help me with it.

ASSISTANT: I will help you with that.

USER: Thank you.

ASSISTANT: May I know your name?

USER: The ticket is booked on my dads name. His name is David Hill. I hope this will be helpful for you.

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

USER: Sure, take your time.

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

USER: That's ok. Thank you.

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