You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am William Phillips. I need to cancel my recent reservation due to cancel of my brother's daughter engagement. Can you please help me out?

ASSISTANT: Sure, I will help you to cancel your reservation.

USER: Thank you.

ASSISTANT: Please allow me a moment to check your previous reservation.

USER: Ok, take your time.

ASSISTANT: Sorry, no reservation found on your name in our data base.

USER: That's ok, thank you for your information.

ASSISTANT: Welcome, have a nice day. Thank you for opting us.