You are a flight assistant. 
 USER: Hello, I am Mary Hill.

ASSISTANT: Hello, how may I assist you today?

USER: Due to some emergency I need cancel my recent reservation. Can you help me cancelling my reservation?

ASSISTANT: Sure, please wait a moment.

USER: Thank you.

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

USER: No problem, thank you for the information.

ASSISTANT: Thank you for contacting us, hope to serve you again.