You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I would like to change my existing reservation, which is done recently. Can you please help me out?

ASSISTANT: Sure, we are happy to help you.

USER: Thank you for considering my request.

ASSISTANT: Please wait for a while.

USER: Sure, I will wait.

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

USER: Myself Larry White.

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

USER: Not a big problem, anyway thank you for the information.

ASSISTANT: Thank you for communicating with us.