You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Laura Campbell.

ASSISTANT: May I know your good name, Please? How can I help you, Laura Campbell?

USER: I want to change my existing reservation as my exam got postponed.

ASSISTANT: We are very sorry to inform you that, There is no reservation found on Laura Campbell.

USER: Ok, no issues.

ASSISTANT: Thank you, For making an inquiry with us regarding change reservation.

USER: Thank you.

ASSISTANT: Have a great day.