I was on version 3.1.22. As usual, I wanted to install the update on Craft CMS 3.1.23. So I clicked Install and got this error:
But that was not all ... My complete vendor/craftcms/cms folder has been deleted. The solution to get back to the CP and the frontend, was to manually upload 3.1.22 back to the folder. When I started the update again - same error. In the while, I have manually updated to 3.1.24. However, I can no longer update plugins or install new ones. The CMS folder is deleted every time.
Does anyone have a similar problem or idea how to solve this? Thanks!