Progress bar not loading

Hi,

Plugin used to work fine, but i noticed that the progressbar is not loading anymore.
The console error in chrome dev tools gives this:

DevTools kan bronkaart niet laden: Kan content voor https://dtok.nl/wp-content/plugins/quiz-master-next/js/progressbar.min.js.map niet laden: HTTP-fout: statuscode 404, net::ERR_HTTP_RESPONSE_CODE_FAILURE

thanks

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