You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I help you?

USER: I am Joshua Campbell.

ASSISTANT: What can I do for you Joshua Campbell?

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

ASSISTANT: Sure, let me check the database and revert you.

USER: Sure.

ASSISTANT: We could not find any reservation by your name.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for picking us.