Bug No Environments

Hello,
I'm confused about the lack of environments in the Simulation view.
In every tutorial I follow, in Simulation View I can see that there are always simulated environments, but in mine there isn't anything.
I tried with Unity 2019 and 2020, same result: no environments, despite the fact that in ContentManager window I have installed the Basic simulation Environment Pack (see attached image).
In my Simulation view, I got only a floor plane and a wall plane, that's all. The environment is called "Default environment" (see attached image).
If I search for "l:Environment" in my project window, like this page suggest, I got no results (see attached image).

Am I missing something?

 

Hello, I created a new project again and install everything in the Content Manager: no Environment installed.
Then, I created again a new project, but this time I install only Basic Simulation Environment Pack from the ContentManager, and now I can see the enviroments.
I think there should be a bug with the way the ContentManager Install every module, maybe there are some conflicts that don't allow the Environments to show up!