You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I assist you?

USER: I am Joseph Martinez, my business meeting were postponed, so I want to change my existing reservation.

ASSISTANT: Sure. Please wait for a moment, I will check the status and revert you.

USER: Sure.

ASSISTANT: Unfortunately, we did not found any reservation on your name.

USER: Not an issue, thank you for your service.

ASSISTANT: Thanks for choosing us.