Low fill rates come from three places: provider gaps, thresholds set too high, or unmatchable input records. Diagnose with the fill-rate report, then fix the specific cause.
Read the fill-rate report
Data → Enrichment → Fill Rates. Per field: % filled, per-provider contribution, and % blocked by threshold. This tells you immediately whether the gap is coverage, thresholds, or matching.
Provider gaps
If all providers return nothing for a field on a segment (e.g. phone numbers for EU contacts), you need a provider with that specific coverage. Add one specialized provider rather than raising volume on existing ones.
Threshold blocks
If a big share of attempts are "filled but below threshold," your threshold may be stricter than the field warrants. Review a sample of blocked values — if they're mostly correct, lower the threshold a notch.
Matching failures
Enrichment can only fill records it can identify. Records missing both email and domain often can't be matched at all. Fix upstream: capture domain at form-fill, or run identity resolution before enrichment.