You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How can I assist you?

USER: I Want to change my existing reservation. Can you help me with this?

ASSISTANT: Sure, I am here to help you.

USER: I Am Stephen Young.

ASSISTANT: Thank you for providing your name, Please wait a moment I will check the available reservation with your name. Thank you for being online, There are no flights available with your name.

USER: OK That's fine. Thank you.

ASSISTANT: Thank you, Have a nice day.