You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: Owing to an emergency, my hadoop workshop organised by professionals has been postponed. So I had a request to you to change my existing reservation?

ASSISTANT: Sure. May I know your name?

USER: Sure, I had a recent reservation with name Stephanie Carter.

ASSISTANT: There is no reservation found with your name.

USER: Ok, no worries at all. Thank you. I appreciate your kind service.

ASSISTANT: Thanks for choosing us.