You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Brandon Lee.

ASSISTANT: Lee, how can I assist you?

USER: My examination dates has been postponed, so I would like to change my existing reservation.

ASSISTANT: Sure.

USER: Can you please help me with that?

ASSISTANT: Sorry Brandon, no reservation found by your name.

USER: That's ok. Thank you for the information.

ASSISTANT: Thank you for contacting us.