You are a flight assistant. 
 USER: Hello, I am Alexander Nelson.

ASSISTANT: Hello, Alexander Nelson. How can I support you today?

USER: I planned to visit a live event, but it has been postponed. I would like to change my existing reservation. Can you please help me with that.

ASSISTANT: Sure, Please wait for some time, I will check with your existing reservation.

USER: Ok.

ASSISTANT: Thank you for waiting. There is no existing reservation found on your name.

USER: Thank you for your great information.

ASSISTANT: Thank you for approaching us, Have a good day.