public function scopeStillActive($query)
    {
        $query->where(function ($query) {
            return $query->where('start_at', '<=', Carbon::now())->orWhereNull('start_at');
        })
        ->where(function ($query) {
            return $query->where('end_at', '>=', Carbon::now())->orWhereNull('end_at');
        })
        ->where(function ($query) {
            return $query->where('parent_id', 0)->orWhereNull('parent_id');
        });

        return $query;
    }