I have checked our issue tracker and I can confirm, there are no open issues for ConvertPlus plugin.
Please make sure that you're fully updated including X theme, Cornerstone plugin by referring to latest versions here (https://theme.co/changelog/) and also update the other plugins by following our version information here (https://theme.co/apex/forum/t/troubleshooting-version-compatibility/195). You can also refer to our update guide if necessary (https://theme.co/apex/forum/t/setup-updating-your-themes-and-plugins/62).
Then you can refer to our knowledge base section on how to use ConvertPlus plugin (https://theme.co/apex/forum/t/extension-convertplus/66).
If you're using a caching plugin, make sure to purge your server cache and also clear your browser cache before testing.
In case if you're having further difficulties, please provide us with your WordPress login credentials in a secure note to check your issue further.
Let us know how it goes.