[SOLVED]Laravel 5.4 Internal error: Failed to retrieve the default value

I have a form which submits data to the database. And it submits data to the database. But Laravel yields an error when it tries to redirect it to another method in the same controller.

ReflectionException in RouteDependencyResolverTrait.php line 57:
Internal error: Failed to retrieve the default value

Here is the controller I use. Please check the public function store(Request $request) method.

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Inbox;

class ContactUsController extends Controller
{
    /**
     * Display a listing of the resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function index()
    {
        //
    }

    /**
     * Show the form for creating a new resource.
     *
     * @return \Illuminate\Http\Response
     */
    public function create()
    {
        return view('pages.contactus');
    }

    /**
     * Store a newly created resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Illuminate\Http\Response
     */
    public function store(Request $request)
    {
        // validate the data
        // store the data in the database
        // redirect to another page
        $this->validate($request, [
            'name' => 'required|max:255',
            'email' => 'required',
            'telephone' => 'required',
            'message' => 'required',
        ]);

        $inbox = new Inbox;

        $inbox->name = $request->name;
        $inbox->email = $request->email;
        $inbox->telephone = $request->telephone;
        $inbox->message = $request->message;
        $inbox->isnew = 1;
        $inbox->category = $request->category;

        $inbox->save();

        // redirects to the route
        //return redirect()->route('contactus.show', $inbox->id);

        return redirect()->action(
            'ContactUsController@show', ['id' => 11]
        );

    }

    /**
     * Display the specified resource.
     *
     * @param  int  $id
     * @return \Illuminate\Http\Response
     */
    public function show($id)
    {
        print_r($id);
    }

    /**
     * Show the form for editing the specified resource.
     *
     * @param  int  $id
     * @return \Illuminate\Http\Response
     */
    public function edit($id)
    {
        //
    }

    /**
     * Update the specified resource in storage.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  int  $id
     * @return \Illuminate\Http\Response
     */
    public function update(Request $request, $id)
    {
        //
    }

    /**
     * Remove the specified resource from storage.
     *
     * @param  int  $id
     * @return \Illuminate\Http\Response
     */
    public function destroy($id)
    {
        //
    }
}

And I tried, both of following methods in two different occasions. But Laravel shows the same error each time.

return redirect()->route('contactus.show', $inbox->id);

return redirect()->action(
   'ContactUsController@show', ['id' => 11]
);

And here is the route file web.php.

Route::get('contactus', 'ContactUsController@create');
Route::get('contactus/show', 'ContactUsController@show');
Route::post('contactus/store', 'ContactUsController@store');

I have no idea what cause this problem. Any suggestion will be helpful.
Thanks!


via Isuru