I refer you to the response I gave in reply #24 in this thread.
You are not bound by the ignorant and moronic response given by the POPLA assessor. Do not pay anything. Ignore all subsequent debt recovery letters.
Debt collectors are powerless to do anything except to try and persuade the low-hanging fruit on the gullible tree to pay up out of ignorance and fear.
Come back when you receive a Letter of Claim (LoC).