You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I support you for the day?

USER: My friend birthday party place has been changed to Las Vegas. Can you please change my existing reservation?

ASSISTANT: Sure, I am happy to help you.

USER: Thank you.

ASSISTANT: May I know your name to check your previous reservation?

USER: Sure, I am Charles Wilson.

ASSISTANT: Please, wait for a while.

USER: Sure.

ASSISTANT: Thank you for being patience. I am here to inform you that, there is no reservation found on your name.

USER: Ok, no issues. Thanks for your help and support.

ASSISTANT: Thank you for approaching us.