You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you now?

USER:  I am Richard Walker want to cancel my reservation due to prepone of my exams. Can you help me in cancelling?

ASSISTANT: Sure, I am glad to assist you in flight ticket cancellation process.

USER: Thank you.

ASSISTANT: Please allow me a moment.

USER: Ok.

ASSISTANT: Thank you for waiting, there is no reservation found in our data base to cancel your flight ticket booking.

USER: Ok, not a problem. Thank you for your response.

ASSISTANT: It's my pleasure to help you and thank you for approaching us.