You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Dennis Wilson.

ASSISTANT: How can I help you?

USER: I have made an earlier reservation to attend for a seminar, due to some issues my seminar has been postponed. Can you please help me in changing my reservation?

ASSISTANT: Yes, I can help you.

USER: Thank you.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: Not a problem, thanks for checking.

ASSISTANT: Thank you for reaching us.