You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: Please change my existing reservation which I have done with my name Betty Nelson.

ASSISTANT: Betty, let me check for your reservation status in our website.

USER: Sure, get back with the status of my reservation.

ASSISTANT: Sorry Betty, I have not found any reservation by your name in our website.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you so much for contacting us and have a nice day.