You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Mark Williams, I want to cancel my reservation which I have done last week. Can you please help me about it?

ASSISTANT: Sure, just a moment please. I am sorry no reservation found on your name.

USER: That's ok, anyway thank you for the help.

ASSISTANT: Thank you for your help.