Settings are not saved

Hei
I noticed, that the checkboxes gets unchecked. I save the settings, with the checkbox for “Require name” ticked. In the next tab “Notifications”, I save the settings as well. Doing that, resets the options from the “Messages” tab
Also, the preview colors are different from the actual color. The header background for example, gets replaced in the preview, but not in the frontend.
Best, Daniel