LIvewire preserving variable

Hi... got a problem but I think it's my lack of understanding.

I have a database of Things. Users of my app can add comments to Things. The comment adding part is just a livewire bound text box with a submit button. I want all the added comments for that Thing to be displayed under the text box. The list of comments should be updated in real time after a new comment is added - Livewire style!

The main controller passes $thing['id'] to the livewire component which looks like this:

public string $comment;

public $thing;

public function addComment()
{
    Comments::create(['
        'artefact' => $this->thing,'
        'user_id' => Session::get('userid'),
        'text' => $this->comment,

    ]);

    $this->reset();
}

public function render()
{
    return view('livewire.thing-comments', [
        'comments' => Comments::where('artefact', $this->thing)->orderBy('created_at', 'DESC')->get(),
    ]);
}

The blade component just foreaches through comments after the text box.

What's happening is that as soon as a new comment is entered, the entry goes into the database but the comment list comes back empty. It appears correct if I refresh the whole page (F5). The problem seems to be that $this->thing is now no longer defined when render() is called again, thus the search returns nothing.

If I hard code the Thing ID into the query at the end, it behaves as required (obviously though it's bound to the one thing).

How can I make Thing persist?