make sure your on the latest version of CB2023 (v23.0.0.1841), just download the revised CB2023 program installer from your online account here to get it: https://www.comicbase.com/mycb/Registrations.aspx
If that doesn't solve you're problem, do you have any other protection software (ex: Norton, MacAfee, AVast, etc.) that could be blocking out ComicBase from internet access? You may need to manually setup a program exception just in case within such software.