You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Can you help me to cancel my reservation?

ASSISTANT: Sure, may I know your name please?

USER: I am Sandra Walker.

ASSISTANT: Wait a while, kindly.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found for the user name in our data base to cancel your previous booking.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for opting us.