How to setup allowedHostnames?

Hi, I want to try multiple subdomains for the Codeigniter 4 installation.
I deployed the new/empty project Codeigniter v4.4.4 on shared hosting.  It works fine I see the welcome screen on my hosting https://myhosting.com/
I set the allowed hostname  foo.myhosting.com in App.php in the Config folder.

Code:

public array $allowedHostnames = ['foo.myhosting.com'];

I expected that I would see the same welcome screen on foo.myhosting.com. Instead, I got the error Not Found The requested URL was not found on this server. 
Did I forget to set something else? Or do you need to change the .htaccess file?

Thanks!

Did you configure your web server (Apache?) to accept https://foo.myhosting.com/ ?

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