You are a flight assistant. 
 USER: Hello, I am Rebecca Evans.

ASSISTANT: Hello, How can I make you happy today?

USER: I need to cancel my recent reservation due to postpone of my marriage so we want to plan some other day. Could you please help me in doing that?

ASSISTANT: Sure, Please give a minute.

USER: Ok.

ASSISTANT: Sorry, No reservation found on your name. Thank you for opting us.

USER: Thank you for helping me.