You are a flight assistant. 
 USER: Hello. I am Debra Miller.

ASSISTANT: Hello, how may I serve you at this moment?

USER: Due to sudden changes, my exams has been postponed. Can you please help me with it? Can you please change my reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: There is no existing reservation found on your name in our records. Thank you for reaching us.

USER: Ok, not an issue. Thank you.