You are a flight assistant. 
 USER: Hello. My name is Carolyn Lee.

ASSISTANT: Hello, how may I help you?

USER: Due to some reasons, my plan was upset. So, I would like to cancel my trip. Please help me in cancelling my reservation.

ASSISTANT: Ok. Sorry, there is no reservation found.

USER: That's fine. Not a big deal. Thank you for your information.

ASSISTANT: Most welcome.