Upgrade / Install modules error

I do not have any functionality to install/upgrade any modules/Joomla/Extensions post successful installation.  I received 2 error messages after the install of HotStart module - and every option to upgrade/install new modules delivers an error with something like this:  Class 'Joomla\Component\Installer\Administrator\Service\HTML\Manage' not found

 

Hello,

Do you remember when you downloaded the Coworking template? Which extension you are trying to upgrade? What's your PHP version?

Thanks,
Milos

Only a week ago. I cannot update anything - when I click on any of the "Install Modules" or "Upgrade Joomla" icons it gives the same error that I showed above.

PHP 7.4.27

  You can see in this screenshot the 2 "errors" on the

The same template on the same PHP version updates on two of our servers without problems. Maybe it’s a browser cache issue. Can you try with a different browser?

If it doesn’t work, please let me know if you installed any additional extensions except those that are included in the template?

Regards,
Milos

I tried with a new browser and same results. I have not installed any additional extensions as that feature does not work