You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Matthew Perez.

ASSISTANT: Nice to meet you, how can I help you?

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

ASSISTANT: Ok, please wait for a while.

USER: Ok, take your own time.

ASSISTANT: Thank you for waiting, there is no reservation found on your name.

USER: That so sad.

ASSISTANT: Do you have any other plans to travel?

USER: No. Anyway, thank you for checking.

ASSISTANT: Thank you for approaching us, have a nice day.