You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I will be cancelling my tickets, which I have booked last week. Can you help me?

ASSISTANT: Sure, please mention your name for further process?

USER: My name is Anna Phillips.

ASSISTANT: Anna, please wait for a moment.

USER: Is there any charges for the cancellation, let me know?

ASSISTANT: Sorry Anna, there is no reservation found on your name to cancel your reservation.

USER: That's fine, thank you for assisting me.

ASSISTANT: You are welcome.