> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sequenzy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Resume A/B Test

> Keep testing a sequence A/B test after a winner was picked

Resume a sequence A/B test that already has a winner, for example one picked
automatically before you were sure. The winner is cleared and contacts who
reach the step are split across the variants again. Results collected so far
are kept, and contacts who already got a variant keep it.

Automatic selection is turned off for the test (`autoSelectWinner: false`), so
it keeps splitting until you choose a winner with
[Select A/B Test Winner](./select-winner). You can turn it back on with
`autoSelectWinner: true` on [Update A/B Test](./update). The test returns to
`testing`, so its variants stay fixed until a winner is selected. Repeating the
request is safe.

## Request

<ParamField path="abTestId" type="string" required>
  Sequence A/B test ID.
</ParamField>

<ParamField body="confirmLiveChange" type="boolean">
  Required as `true` when the sequence is active, because contacts reaching the
  step are split again from then on. Not needed to repeat a resume that already
  applied.
</ParamField>

```bash theme={null}
curl -X POST "https://api.sequenzy.com/api/v1/ab-tests/ab_abc123/resume" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"confirmLiveChange":true}'
```

The API key needs `ab_tests:write` and `sequences:write`.

## Responses

<ResponseExample>
  ```json 200 theme={null}
  {
    "success": true,
    "abTest": {
      "id": "ab_abc123",
      "kind": "sequence",
      "status": "testing",
      "winningVariantId": null,
      "autoSelectWinner": false
    }
  }
  ```

  ```json 400 theme={null}
  {
    "success": false,
    "error": "Resuming an A/B test in an active sequence requires confirmLiveChange=true"
  }
  ```
</ResponseExample>

400 also covers campaign tests, completed or cancelled tests, a test that is no
longer attached to its step, and a test with fewer than two variants; 401/403
cover authentication, scope and role restrictions; 404 means the test is
unavailable.