The error message "Unable to use the PHP Selector for user: Cannot manage PHP versions when CageFS is disabled" suggests that the PHP Selector feature in your hosting environment relies on CageFS for managing PHP versions for individual users. CageFS provides a secure environment for each user by encapsulating them within their own file system.

If CageFS is disabled, you won't be able to use the PHP Selector to manage PHP versions on a per-user basis.

Here's what you can do:

1. Enable CageFS:

   The most straightforward solution is to enable CageFS on your server. This will allow you to continue using the PHP Selector feature.

2. Check Hosting Environment Compatibility:

   Ensure that all components of your hosting environment are compatible with CageFS. Some environments may have specific requirements for CageFS to function properly.

3. Contact Hosting Provider:

   If you're on a shared hosting environment, contact your hosting provider or server administrator for assistance. They may be able to enable CageFS for you.

4. Explore Alternative Solutions:

   If enabling CageFS is not an option, consider using other methods or tools for managing PHP versions. This could include using MultiPHP Manager (if available in cPanel), or manually adjusting PHP settings at a server-wide level.

5. Migrate to a Different Hosting Environment:

   If CageFS is a requirement for your specific needs, consider moving to a hosting environment where CageFS is enabled by default or where you have the ability to enable it.

Remember, if you're unsure about any changes you're making, especially at a server level, it's always a good idea to consult with your hosting provider or server administrator for guidance. They can provide specific recommendations based on your server's configuration and environment.