You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Helen Moore here, due to sudden changes my exams has been preponed. Can you please change my reservation?

ASSISTANT: Sure, I am gleeful to help you. Please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, we are sorry to say that no reservation was found in our database on your name.

USER: Not an issue, thank you.

ASSISTANT: Thanks for choosing us.