Your question is Troubleshoot Broken Third-Party Pipeline. Take a moment with it on the right.
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You are responsible for a data pipeline that depends on data from an external vendor. One day, the integration stops delivering usable data, and downstream users start seeing stale or missing records. You need to work through the failure methodically, isolate where the break happened, and restore the pipeline without creating duplicates or bad backfills.
How do you troubleshoot a third-party integration that suddenly stops working?