Unable to inherit x-corporation theme, Grav stop with error

Hello,

1. I inherited x-corporation with mytheme but I get the error:

"Class 'Grav\Theme\Xcorporation' not found"

1. The problem Is in the php file, user/themes/mytheme/mytheme.php has:

<?php
namespace Grav\Theme;

class mytheme extends Xcorporation
{
   // Some new methods, properties etc. 
}
?>

1. Grav works fine with the original X-Corporation theme, it creates a folder: user/themes/x-corporation with the following file: x-corporation.php

<?php
namespace Grav\Theme;

use Grav\Common\Theme;

class Xcorporation extends Theme
{
}
?>

1. I found on the forum this same topic from 2017 with no solution:
   /forum/archive/theme-inheritance-problem-extending-parent-theme-t970

   But I need to extend x-corporation theme and I do not find the way to solve this error, any help is appreciated.
   Thanks and regards.
   joejac

@joejac, I cannot reproduce the issue....

Using a fresh install of Grav + Admin:

• I installed X-Corporation using $ bin/gpm install x-corporation
• Created inheriting theme 'mytheme' using bin/plugin devtools new-theme
• Updated /user/config/system.yaml to set theme to 'mytheme'
• Fired up the browser and all is well...

Hello and thanks @pamtbaau
I do not know what to say, perhaps is my Centos 7 VPS that has several php versions and I had to inherit manually, because bin/plugin devtools new-theme does not run on my VPS.
I am working without the class in the php file, I know it is not correct but It stopped the error.
Thanks for your time to test.
Regards
joejac