Sorry that you're having that issue but we cant mark this as a bug for now as I can't replicate the issue on my dev site. I can't log in with the credentials you provided now, please make sure you're all up to date.
- Wordpress 5.3
- X 7.1.1
- Cornerstone 4.1.1
- Modern Events Calendar 4.8.3
- Under Construction 2.0.5
Updating Your Themes and Plugins
Remember to clear all your caching features (plugin, server-side, CDN, and browser's cache) after updating so that the code from the latest release is always in use. This will help you to avoid any potential errors.
Let us know how it goes,