You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I guide you for today?

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

ASSISTANT: May I know your name, please?

USER: I have reserved my flight ticket with name Scott Perez.

ASSISTANT: Please give me a minute, I will find your existing reservation.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: Ok, fine thank you for your help.

ASSISTANT: Thank you for contacting us, have a nice day.