You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I'm Donna Hall.

ASSISTANT: Yes.

USER: I want to cancel my reservation, will you help me out?

ASSISTANT: Sure, please give some time to check the details.

USER: OK.

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

USER: Thank you for your immediate response.

ASSISTANT: Want to have any more information please?

USER: No thanks.

ASSISTANT: OK, thank you and have a nice day.