Data leak

n8n is writing duplicate leads into your CRM

The same person shows up two or three times in your CRM. It looks like a CRM problem, but it usually starts upstream in the workflow.

Why it happens

There's no 'Remove Duplicates' step (or dedupe by a unique key), so retries, double submits and re-runs each write a fresh record.

How to fix it

Add a 'Remove Duplicates' step, or dedupe by a unique key like email, before the node that writes the lead.

How to verify

Submit the same lead twice and confirm only one record is created downstream.

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