You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you?

USER: I want to change my existing reservation due to postpone of my exams, can you help me with that?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Can I know your name please?

USER: I am Virginia Taylor.

ASSISTANT: Sorry to inform you that there is no active reservation on your name.

USER: Ok, not an issue. Thank you for checking.

ASSISTANT: Thanks for reaching us, have a nice day.