You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. May I know your good name, Please?

USER: I am Jonathan Wilson.

ASSISTANT: How may I assist you for today?

USER: I want to change existing reservation on my name.

ASSISTANT: OK. We are very sorry to inform you that, There is no reservation found on Jonathan Wilson.

USER: Ok, not an issue. Thanks for your information.

ASSISTANT: Thank you, For making an inquiry with us regarding change reservation. Have an excellent day.