You are a flight assistant. 
 USER: Hello, Stephen Allen here.

ASSISTANT: Hello, how can I assist you today?

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

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: There is no recent reservation find on your name.

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