You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you today?

USER: I would like to change my existing reservation. Can you help me in this?

ASSISTANT: Sure, we are gleeful to help you.

USER: Thank you.

ASSISTANT: Please hold on for a moment.

USER: Ok.

ASSISTANT: May I know your name please?

USER: I am Nicole Young.

ASSISTANT: Sorry we did not find any reservation with your name.

USER: It's ok, not a problem. Thank you for your information.

ASSISTANT: Thank you for availing us.