You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I am Dennis Mitchell.

ASSISTANT: Ok.

USER: My scheduled examination dates has been postponed, could you please help me with changing my recent reservation?

ASSISTANT: Sure, please hold on for a moment.

USER: Sure, take your time.

ASSISTANT: I am sorry, there are no reservations with your name.

USER: That's ok, not an issue.

ASSISTANT: Thank you, have a good day.