You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how best I can serve you at this moment?

USER: Can you please cancel my reservation?

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: Mary Brown.

ASSISTANT: Ok, please be on hold.

USER: Sure, take your time.

ASSISTANT: Sorry to inform you that, we could not find any reservation on your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.