Http客户端post返回400错误Laravel 7

我有一个卷曲http，我从中复制：

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_PORT => "8080",
  CURLOPT_URL => "http://localhost:8080/engine-rest/process-definition/novello:1:9193cb96-ff50-11ea-9734-0242f038e69f/start",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => "",
  CURLOPT_HTTPHEADER => [
    "content-type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

这很好，但我想使用本文档中描述的Laravel提供的Http：

我看起来像这样：

$uri = 'http://localhost:8080/engine-rest/process-definition/novello:1:9193cb96-ff50-11ea-9734-0242f038e69f/start';
        $headers = [
            'Content-Type' => 'application/json'
        ];
        $response = Http::timeout(10)->withHeaders([$headers])->post($uri);
       return $response->body();

问题是我从请求的端点接收到400个错误

我不想用curl，因为它没有收到帖子后的回复。我需要回复，因为该端点处理了大量文档，有时需要大约1分钟才能完成