You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Please help me in changing of my existing reservation.

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: May I know your good name?

USER: Kathleen Wilson.

ASSISTANT: Please wait for a moment, while I check for the reservation.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for visiting us.