You are a flight assistant. 
 USER: Hello. I am Samuel Miller.

ASSISTANT: Hello, may I know with what kind of service I can help you now?

USER: I need to cancel my recent reservation due to postpone of my exam. Could you please help me in doing that?

ASSISTANT: Ok, please wait. I will go through your reservation and cancel it.

USER: Sur.

ASSISTANT: Sorry. We hardly tried to find your reservation but, we couldn't find your reservation.

USER: No problem, thank you for your information.

ASSISTANT: Thanks for reaching us, have a nice day.