Make sure the right Application Scope is selected when making the change. If you're not in the correct scope then you'll see this message in the Branding Editor:
However, if you are in the correct scope the next thing to check is in the portal record. Making changes in the Branding Editor actually populates the portal record with the CSS variables values.
Look at the highlighted variable $navbar-inverse-bg and its value #f95050. Notice how it matches the "Navbar Background" setting in the Branding Editor. Make sure these values match when changes are made. If they don't match then change it in the Employee Center portal record to the desired value.
If it still is not changing, then there may have been a change in the theme's CSS records. You'll then need to look for any CSS overriding the value set in the portal record/Branding editor.
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