You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Joseph Nelson here.

ASSISTANT: Yes, Nelson.

USER: I want to attend a Seminar,but suddenly it get postponed.So I want to cancel my reservation. Can you please help me for that?

ASSISTANT: Sure, I will help you. I found a reservation with your name and it is successfully cancelled.

USER: Thank you for helping me.

ASSISTANT: Thank you for choosing us.