You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I want to change my reservation as my plan to meet my share holder is postponed. Can you please help me to change it?

ASSISTANT: Sure, can I know your name please?

USER: Sure, my name is Michelle Johnson.

ASSISTANT: Ok, wait a moment please.

USER: Sure.

ASSISTANT: Sorry Johnson, there is no reservation found on your name.

USER: That's Ok, thanks for your assistance.

ASSISTANT: Thank you for approaching us.