Laravel Eloquent Model Does not return anything or show any error

My Eloquent Model is here-

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class UserAdvertisementView extends Model
{
    protected $primaryKey   =   null;
    public $incrementing    =   false;
    public $timestamps      =   false;

    protected $table        =   'user_add_views';           //Table Name

    protected $fillable     =   [
                                    'user_id',
                                    'add_id',
                                    'total_view'
                                ];

    public function user()
    {
        return $this->hasOne('App\User','user_id');
    }

    public function advertisement()
    {
        return $this->hasOne('App\advertisement','add_id');
    }

    //Scope Query for view count
    /**
    * Scope a query for a mass Assignment
    *
    * @return \Illuminate\Database\Eloquent\Builder
    */
   /*
   public function scopeInsertData($query,$project_id,$data)
   {
        $bulk_data = array();
        foreach ($data as $value)
        {
            array_push(
                            $bulk_data,
                            array(
                                    'project_id' => $project_id,
                                    'feature_id' => $value
                                )
                        );
        }
       return $query->insert($bulk_data);
    }
    */
}

And Controller like this-

public function map_try($id)
{
    $result = UserAdvertisementView::where('user_id','=',Auth::user()->id)
                            ->where('add_id',$id)
                            ->first();
    if($result)
    {
        $result->total_view = 90;
        $result->save();
        return $result;
    }
    else
    {
        UserAdvertisementView::create(array(
            'user_id'=> Auth::user()->id,
            'add_id'=> $id,
            'total_view'=>1
        ));
        return 'OK';
    }
}

Problem is, it don't return anything, not even an error or any response.

So, I am getting this-

Can anyone please help?

via Chebli Mohamed