You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I best support you now?

USER: I need to change my existing reservation due to my exams has been postponed. Can you please aid me to change it?

ASSISTANT: Sure, I can help you in that.

USER: Thank you.

ASSISTANT: May I know your good name please to track the details?

USER: My name is Laura Robinson.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: Ok, thanks for your service.

ASSISTANT: Thanks for approaching us, wish you a great day.