You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Paul Green. I want to change my existing reservation due to postponed of my journey.

ASSISTANT: Sure, hold on a minute.

USER: Can you please help me with this?

ASSISTANT: Sure.

USER: Thank you.

ASSISTANT: There was no reservation found on your name.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.