public function apply($builder)
    {
        if (!empty($values = $this->getValues())) {
            $range = json_decode($values, true);
            if (!isset($range['start']) or ! isset($range['end'])) {
                return $builder;
            }
            $start = $range['start'] . ' 00:00:00';
            $end   = $range['end'] . ' 23:59:59';
            $builder->whereBetween('tbl_notifications_stack.created_at', [$start, $end]);
        }
    }