You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation as my conference got rescheduled.

ASSISTANT: Sure, can I have your name please?

USER: I am Stephanie Carter.

ASSISTANT: Ok, please wait I will get back to you.

USER: Ok.

ASSISTANT: Thanks for waiting, no flight reservation found on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for the response.