Using "populate" in addon

Addons
1

I want to use the populate attribute to fetch all the nested collections that my “Payments” collection has, but I’ve tried adding it like this: populate => 1, but it doesn’t work for me.
This is how I get the data, but I need to add the populate attribute:

$data= $app->module('content')->items('payments', [
'sort' => ['_created' => 1],
'limit' => 1,
]);

I am using the latest version of Cockpit available