Laravel passport 获取 token 时无响应？

请求中间件

namespace App\Http\Middleware;

use Carbon\Carbon;
use Closure;
use Laravel\Passport\Client;

class OauthClient
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request $request
     * @param  \Closure $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {
        \Cache::forget("oauth.client");
        if (cache("oauth.client")) {
            $client = cache("oauth.client");
        } else {
            $client = Client::query()->where("name", "Laravel Password Grant Client")
                ->firstOrFail();
            cache([
                "oauth.client" => $client
            ], Carbon::now()->addSeconds(2));
        }

        $request->request->add([
            "scope" => "*",
            "client_secret" => $client->secret,
            "client_id" => $client->id,
            "grant_type" => "password",
        ]);
        return $next($request);
    }
}

响应中间件

namespace App\Http\Middleware;

use App\User;
use Closure;
use Illuminate\Http\Response;
use function PHPSTORM_META\type;

class OauthUserExtra
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {
        $response = $next($request);
//        dd($response);

        $r=new Response();
        if ($response->isOk()){
            $user = (new User)->findForPassport(request("username"));
            $contents = json_decode($response->getContent(),true);
            $contents["user"] = $user;
            $response->setContent($contents);
        }

        return $response;
    }
}

路由

Route::group([
        "middleware" => [
            "oauth.client",
            "oauth.user.extra",
        ]
    ],function (){
        Route::post("oauth/token", "\Laravel\Passport\Http\Controllers\AccessTokenController@issueToken");
    });

是不是nginx单进程的原因？如果是单进程，开多几个进程就可以了。我之前本地测试就遇到过。