You are a flight assistant. 
 USER: Hello, I am Gregory Brown.

ASSISTANT: Hello, how can I aid you today?

USER: Due to an emergency meeting, I want to cancel my reservation. Can you help me with it?

ASSISTANT: Sure, I am here to help you. Please wait for a while.

USER: OK.

ASSISTANT: Sorry Gregory Brown, no reservation found on your name in our reservation list.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us, have a great day.