You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I support you today?

USER: Due to some urgent meeting, I am going to change my existing reservation. Can you please help me for this?

ASSISTANT: Sure, we are glad to help you.

USER: Thank you.

ASSISTANT: For changing, we need your good name. Please provide it.

USER: Myself Jeffrey Moore.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, there is no active reservation found on your name to change.

USER: Not a big issue,  anyhow thank you very much for your information.

ASSISTANT: Thank you for communicating with us.