You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: May I know your name to proceed further?

USER: Daniel Wilson here.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no active reservation found on your name.

USER: That's ok, no problem. Thank you.

ASSISTANT: Thank you for opting us.