You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be of your help today?

USER: I am Melissa King.I need to cancel reservation.

ASSISTANT: Sure Melissa, just hang on a moment. I will check and revert to you.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found against your name.

USER: OK, Thanks for your information.

ASSISTANT: Thanks for giving us an opportunity to help you.