You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: I am Elizabeth Wilson. Could you please change my existing reservation due to postpone of my bord meeting?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, unfortunately no reservation found with provided name.

USER: Not a problem, thank you.