You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I serve you?

USER: I am David Perez. I just want to cancel my recent reservation due to my convocation has been cancelled.

ASSISTANT: Sure, wait for a moment.

USER: Can you please help me with cancellation? Ok.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: Ok, no issue. Thank you for your service.

ASSISTANT: Thank you for choosing us.