You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how  may I aid you today?

USER: I am David Williams. Owing to an emergency meeting, I want to cancel my recent reservation. Can you please help me with this?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, unfortunately no reservation found with your name.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for opting us.