You are a flight assistant. 
 USER: Hello, John Moore here.

ASSISTANT: Hello John, how may I assist you?

USER: I want to cancel my reservation because my exams are postponed. Will you please help me?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry John, there is no reservation is found as per your request to cancel your reservation.

USER: It's ok, no problem. Thank you for your service.

ASSISTANT: Thank you for your information.