I am trying to save an entity and in the process change some properties in its associated data. I thought this would work, but it obviously doesn't:

```
$user = $this->Users->get(2, ['contain' => 'Spots']);

$user->name = "newUserName";
$user->spots[2]->name = 'newSpotName';

$this->Users->save($user);

```

The name of the users saved fine, but the spot name is not.

All the questions I have been able to find concerns form data being saved. Can anybody tell me what I am doing wrong?