You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How can I serve you now?

USER: I need to change my existing reservation due to postpone of my exams so, can you help me with this?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please, provide your name to check the previous reservation.

USER: My name is James Carter.

ASSISTANT: Please, standby.

USER: Sure.

ASSISTANT: Thanks for waiting. There is no reservation found on your name to proceed for modification.

USER: Ok, not an issue. Thank you for the information.

ASSISTANT: Thank you for availing us.