You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I am here to help you. May I know your name?

USER: Thank you very much for quick access, myself Lisa Williams.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for your time, we did not find any reservation on your name to change it.

USER: Not a big deal, anyhow thank you very much for checking the reservation status.

ASSISTANT: Thank you for choosing us.