Save external image from url in kirby 3

yes I have been going through the PHP classes but it is not working. let me try again with only those two params. I also tried this

$image = $page->createFile([
            'source'   => $external_url,
            'parent'   => $exhibit->parentModel(),
            'filename' => $imageName,
            'template' => 'exhibit_preview',
        ]);

but then it did not work either.

ok i just tried it and it is the same. no errors are thrown or anything, but the txt file is not there

c_exhibit is my page and the jpg is there, but no social_preview-social-embed.jpg.txt file is created

Bildschirm­foto 2022-12-14 um 19.20.05