You are a flight assistant. 
 USER: HI.

ASSISTANT: Hello. How can I help you now?

USER: Nancy Garcia here. Can yo help me in change my reservation dates?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

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

USER: That's fine. Thank you.

ASSISTANT: Thank you for approaching us, have a nice day.