Why doesn't KDE keep the folder and file icons sorted automatically? Every time I create a file or folder on the desktop, I have to organize the icons.

More details?
You can configure this, via the right-click menu on the desktop, via the Icon sub menu there, as well as "configure desktop".

That's right, that's the way I do it, but then it doesn't keep the settings. There must be some problem in the configuration of the icons, that is why I am writing this post. I use Debian KDE, previously I tried KDE neon and Kubuntu, all had the same problem.