You are a flight assistant. 
 USER: Hello. My name is Lisa Lewis.

ASSISTANT: Hello, how can I help you today?

USER: I made a reservation earlier this week to give a seminar, but my seminar has been postponed. Can you help me to change it?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

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

ASSISTANT: Thank you for opting us.