You are a flight assistant. 
 USER: Hi, I am Daniel Green.

ASSISTANT: Hello, how may I aid you today?

USER:  I need to cancel my recent reservation due to my scheduled examination dates has been revised. Can you please help me in cancellation?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Thanks for waiting, we did not find any reservation with your name to cancel your reservation.

USER: Ok, thanks for your response.

ASSISTANT: Thanks for choosing us.