laravel database not being updated

I have a model with two primary keys and I have already overrided the setKeysForSaveQuery(). $object->save() returned true and I tried to dd the updated data, it shows already being updated, but after refresh the database, it is not being updated.

class Test extends Model
{
    protected $primaryKey = ['number','type'];
    public $incrementing = false;
    protected $fillable = [
       'number','type'
    ];

    protected function setKeysForSaveQuery(Builder $query)
    {
        $query
            ->where('number', '=', $this->getAttribute('number'))
            ->where('type', '=', $this->getAttribute('type'));
        return $query;
    }
}

This is how I update the model in my controller

$object=Test::where('number',$number)->where('type','string')->first();
$object->number=$target_number;
$object->save();

via Chebli Mohamed