You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Gregory Thomas. Owing to an emergency, my trip is cancelled.

ASSISTANT: Sure.

USER: Could you help me in cancelling the reservation?

ASSISTANT: Give me a moment please. Sorry Thomas, there is no reservation found on your name.

USER: That's ok. Thank you for your time.

ASSISTANT: Thank you for your positive response.