Knowledge base

Title

Troubleshooting duplicate or missing webhook deliveries

Body

Customers on this topic usually report that their webhook endpoint is receiving each event more than once, or not at all, and want to know whether the problem is on their side or ours.

What to tell the customer
1. Confirm which event type and time window they are seeing the issue on, and ask for one example event id.
2. Explain that our delivery layer retries any webhook that does not return a 2xx within the timeout, so a slow or briefly failing endpoint can legitimately receive the same event more than once — their receiver should de-duplicate on the event id.
3. For missing deliveries, have them check their endpoint's recent response codes in the dashboard's Webhook log; a run of non-2xx responses pauses delivery until they re-enable it.

When to escalate
Escalate to a human teammate if the customer confirms their endpoint returned 2xx for every delivery and they still see duplicates after 2026, since that points to a platform-side retry bug rather than normal at-least-once behaviour.

Notes
Webhook delivery is at-least-once, not exactly-once; idempotency on the receiver is the supported pattern.