Webhooks returning 401 since yesterday
Since yesterday morning every webhook delivery to our endpoint fails with 401. Nothing changed on our side, the signing secret is the one from the dashboard. Can you check what is going on?
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12:03:41 ticket #4821 · webhooks returning 401 · sev-2
12:04:05 correlate · 401s match · candidate POST /v1/messages
12:05:12 sandbox replay (mock from openapi) · reproduced 401
12:06:03 cause: signing secret rotated 09:07 · config error
12:07:10 verify · fix replay with rotated secret · 200 ok
12:07:23 verified · reply drafted with sandbox evidence
Illustrative trace.
every reply checked before it ships
01the difference
One ticket. Two kinds of answer.
Hi Maya. 401 errors usually mean an expired API key. Please regenerate your key in the dashboard and update your integration. Let us know if that helps.
Hi Maya. Your webhook signing secret was rotated yesterday at 09:07, so deliveries signed with the old secret are rejected with 401. Update the secret in your webhook settings and deliveries pass again. We reproduced the failure against a copy of your setup and confirmed the fix: the same delivery now returns 200.
02the method
It runs your customer’s broken request in a sandbox and watches it fail.
$ reproloop replay --ticket 4821building sandbox from northwind/api@a31f2c · ready in 6.2sloading the customer’s webhook settings and the failing delivery→POST /v1/webhooks/deliver · signed with the customer’s secret← 401 Unauthorized { "error": "signature_mismatch", "secret_rotated": "2026-09-03T09:07Z" }×failure reproduced · matches the customer’s report
Illustrative replay.
03the proof
Then it fixes the cause and runs the request again until it passes.
webhook delivery · POST /v1/webhooks/deliver
expected 200 · got 401 · signature mismatch
webhook delivery · POST /v1/webhooks/deliver
200 OK · 184 ms · secret updated in webhook settings
illustrative run · if any line fails, the ticket goes to a person · our own published number: coming soon
04the surfaces
The reply lands where your customer wrote to you.
Your webhook signing secret was rotated yesterday at 09:07, so deliveries signed with the old secret are rejected. Update the secret in your webhook settings and deliveries pass again.
reproduced in a copy of your setup · POST /v1/webhooks/deliver · 401 before · 200 after
05the control
You approve each reply from your phone, until you decide it can send on its own.
Billing, refunds, security, and account changes always wait for you.
Reply ready · ticket #4821
Reproduced the 401in a copy of Northwind’s setup and proved the fix. Send the reply to Maya?
reproducedfix provenchecks passed
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06the price
You pay for verified replies. Nothing else.
| verified replies sent | 37 of 40 included | $0 |
|---|---|---|
| replies you held | 12 | $0 |
| replies that failed the checks | 9 | $0 |
| sandbox runs | 128 | $0 |
| plan · self-serve | $99.00 |
$2.50 for each verified reply beyond your plan · hosted in the EU · illustrative statement
07deliver
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RESOLVED · VERIFIED
Every webhook delivery to our endpoint fails with 401 since yesterday. Nothing changed on our side.