We are using the vue-bulma-admin scaffold on a project, which already uses webpack, and we can't seem to perform any POST/PUT requests to our API (which already sets access-cross-allow-origin headers to *), only GET requests works. From different front-ends that consumes our API, we don't have this problem, only with this specific front-end, which gives as this common error:
"No 'Access-Control-Allow-Origin' header is present on the requested resource."
Response to preflight request doesn't pass access control check: 
No 'Access-Control-Allow-Origin' header is present on the requested 
resource.
We already tried to set custom headers on axios/vue-resource, but with no success. As I said, using the same routes through Postman / different front-ends or with the CORS chrome extension, everything works fine.
Any ideas to work around this?
My Middleware Cors in Laravel API.
<?php
namespace App\Http\Middleware;
use Closure;
class Cors
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {
        return $next($request)
          ->header('Access-Control-Allow-Origin', '*')
          ->header('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE, OPTIONS');
    }
}
