Tips on minimizing false positives when detecting rare events?

TLDR; I have a text deduplication model running at 98% accuracy on >680 million combinations, thresholded to evenly balance sensitivity and specificity. Duplicates occur at a rate <0.5%, which means that most detections are false positives. Is there any way to reduce the rate of false positives without losing the signal?

— Full story —
I’m working for a large company that uses advertising brand names. I’ve been asked to create a model that detects duplicate names in a database …

accuracy datascience deduplication events false rate reduce running signal text tips