You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I need cancel my reservation because my exam has been postponed and no yet rescheduled again. can you cancel my reservation?

ASSISTANT: Sure, I will help you.

USER: Myself Karen Moore.

ASSISTANT: I found your reservation and it is successfully cancelled.

USER: Ok, thank you so much.

ASSISTANT: Thank you for choosing us.

USER: Welcome.