When invoice numbers do not add up, pull the usage event error export and filter by error type. Missing billable metric means the event_type was not wired up; missing price means the metric exists but has no rate for the event. Treat received-after-finalization as a grace period problem, not a rating bug.

Context: Official docs (Metronome rated events / data export guide): documents the usage event error taxonomy surfaced via data export: duplicate event, invalid event format, missing customer, missing contract, missing billable metric, missing product, missing price, plus received-after-finalization for late events.