Every site I have loads just fine with the Epik theme. Since they’re all on different servers and working fine, I’d have to assume there must be something else interfering. Can you double check all of your plugins by deactivating each one to see if they have an effect.
Also check any custom Code that you may have added as that could also have an effect.
You could also reinstall WordPress through the WP admin and see if that works.
The Epik theme itself doesn’t include any code that would prevent the WordPress Customizer from working. Make sure you’re using the latest version of Epik if you haven’t made any customizations to your theme files directly.
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