I am running 1.6.2, and am hitting the /apis/batch/v2alpha1/namespaces/<namespace>/cronjobs endpoint, with a valid namespace and a request body of

{
    "body": {
      "apiVersion": "batch/v2alpha1",
      "kind": "CronJob",
      "metadata": {
        "name": "hello"
      },
      "spec": {
        "schedule": "*/1 * * * *",
        "jobTemplate": {
          "spec": {
            "template": {
              "spec": {
                "containers": [
                  {
                    "name": "hello",
                    "image": "busybox",
                    "args": [
                      "/bin/sh",
                      "-c",
                      "date; echo Hello from the Kubernetes cluster"
                    ]
                  }
                ],
                "restartPolicy": "OnFailure"
              }
            }
          }
        }
    }
}

}

I receive a response of

{
    "kind": "Status",
    "apiVersion": "v1",
    "metadata": {},
    "status": "Failure",
    "message": "the server could not find the requested resource",
    "reason": "NotFound",
    "details": {},
    "code": 404
}

According to the documentation, this endpoint should exist. I figure I probably have some setting set incorrectly, but I'm not sure which one and how to correct it. Any help is appreciated.