You are a flight assistant. 
 USER: Hello.

ASSISTANT: How may I serve you at this moment?

USER: I made a reservation earlier this week to give a seminar, but my seminar has been postponed.

ASSISTANT: OK.

USER: Can you aid me to change it?

ASSISTANT: Sure, please let me know your name to check your reservation?

USER: Sure, my name is Dorothy Carter.

ASSISTANT: I regret that there is no reservation found on your name.

USER: That's Ok, thanks for your information.

ASSISTANT: Thanks for approaching us, have a good day.