You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you now?

USER: I am Anthony Lee. I need to change my existing reservation, can you please help me with that?

ASSISTANT: Sure Anthony Lee, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait a moment to check your reservation status.

USER: Sure.

ASSISTANT: Sorry Anthony Lee, no reservation has found under your name to change.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for choosing us, have a good day.