You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you today?

USER: Please change my existing reservation.

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your good name?

USER: I am Lisa Thompson.

ASSISTANT: Please, wait.

USER: Ok.

ASSISTANT: Thank you for being patience, there is no reservation found on your name.

USER: Ok, Thanks for the information.

ASSISTANT: Thank you for availing us.