Upload delete files

[dv3xxx-git]

Hi, I have a problem with the downloaded files.
I can't delete files because of this error, it seems that I did everything according to the documentation.

SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails (example_app.attachmentable, CONSTRAINT attachmentable_attachment_id_foreign FOREIGN KEY (attachment_id) REFERENCES attachments (id) ON DELETE CASCADE ON UPDATE CASCADE) (SQL: insert into attachmentable (attachment_id, attachmentable_id, attachmentable_type) values (75, 1, App\Models\ApiUser))

My update method:
` public function createOrUpdate(ApiUser $api_user, Request $request)
{
$api_user->fill($user)->save();

    $api_user->attachment()->delete();`

    $api_user->attachment()->syncWithoutDetaching(
        $request->input('api_user.attachment', [])
    );

    Alert::info('success ' . $this->addText);

    return redirect()->route('platform.api.user.list');
}`