Drafts from Virtual page (Database) not showing in Panel

1

I have a site that uses a database. Everything works but the draft status is saved in the database as ‘null’ and is then not visible in the panel. I used the guide: Content from a database | Kirby CMS

This is the model:

$entries[] = [
                'slug'     => $entry->slug(),
                'num'      => $entry->status() === 'listed' ? 0 : null,
                'template' => 'portfolioitem',
                'model'    => 'portfolioitem',
                'content'  => [
                    'title' => $entry->title(),
                    'uuid'  => $entry->id(),
                    'status' => is_null($entry->status()) ? 'draft' : $entry->status(),
                ]
            ];

protected function changeStatusToDraft(): static
    {
        $data['status'] = 'null';

        if ($comment = Db::first('portfolio', '*', ['slug' => $this->slug()])) {
            Db::update('portfolio', $data, ['slug' => $this->slug()]);
        }

        return $this;
    }

    protected function changeStatusToListed(int|null $position = null): static
    {
        // create a sorting number for the page
        $num = $this->createNum($position);

        // don't sort if not necessary
        if ($this->status() === 'listed' && $num === $this->num()) {
            return $this;
        }

        $data['status'] = 'listed';

        if ($comment = Db::first('portfolio', '*', ['slug' => $this->slug()])) {
            Db::update('portfolio', $data, ['slug' => $this->slug()]);
        }

        if ($this->blueprint()->num() === 'portfolioitem') {
            $this->resortSiblingsAfterListing($num);
        }

        return $this;
    }

    protected function changeStatusToUnlisted(): static
    {
        if ($this->status() === 'unlisted') {
            return $this;
        }

        $data['status'] = 'unlisted';

        if ($comment = Db::first('portfolio', '*', ['slug' => $this->slug()])) {
            Db::update('portfolio', $data, ['slug' => $this->slug()]);
        }

        $this->resortSiblingsAfterUnlisting();

        return $this;
    }

    public function isDraft(): bool
    {
        return in_array($this->content()->status(), ['listed', 'unlisted']) === false;
    }