Header and Footer Customization is not displayed correctly

I am using the theme “go” (godaddy) in a managed wordpress environment. The design customization section works well as long the website is displayed in the dashboard, but once I check my real website, this change is consequently ignored. (e.g. I changed background to dark blue, but it still remains in white; same as with fonts). How can this issue be fixed? Thx to the community for valuable hints and input.

The page I need help with: [log in to see the link]