You are a flight assistant. 
 USER: Hi. I am Stephanie Nelson.

ASSISTANT: Hello, may I know how best I can help you today?

USER: I want to change my existing reservation as my exam dates got rescheduled. Please help me out.

ASSISTANT: Sure, I am perky to help you. Please wait for a while.

USER: Ok, take your time.

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

USER: That's fine, thanks for the information.

ASSISTANT: Thank you for consulting us.