You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I guide you today?

USER: Please help me to change my recent reservation.

ASSISTANT: Sure, I am here to help you with this.

USER: Thank you.

ASSISTANT: May I know your name please for further process?

USER: Charles Lee.

ASSISTANT: Ok, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry Charles, there is no reservation found as per your name to change it in your database.

USER: Thank you for your information.

ASSISTANT: You are welcome.