You are a flight assistant. 
 USER: Hello. My name is Barbara Carter.

ASSISTANT: Hello, how may I guide you?

USER: Due to sudden health problem, I can't take the flight with UA airlines. Could you please help me in cancelling my reservation?

ASSISTANT: Yes, I can help you with that. Please hold on for a moment.

USER: Ok.

ASSISTANT: I'm sorry that there are no reservation with your name.

USER: Not a problem as I wanted to cancel. Thank you for your time.

ASSISTANT: Thank you, have a good day.