You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you for the day?

USER: Benjamin Miller here. I want to change my existing reservation due to my board exams. Can you help me for this one?

ASSISTANT: Sure, I am here to help you with that. Please hold for a moment, let me check your previous reservation status.

USER: Sure.

ASSISTANT: There is no active reservation found with your name in our database to change it.

USER: No issues, thank you for your information.

ASSISTANT: Thank you for reaching us, have a great day.