Probably this is not an issue anymore for you. But as I just ran into the same issue and managed to solve it, I wan to share it for others that could look into this post.
I just followed the steps in this other post., with few (and don’t really needed) additions:
1. Login to file manager in cPanel. Or via FTP to your WordPress installation.
2. Find the plugins directory (for example under public_html/wp-content/plugins).
3. Rename the name of this plugin “remove-dashboard-access-for-non-admins” to any other name, let’s say to “remove-dashboard-access-for-non-admins-REMOVED”.
4. Then close the browser and open it again and login to your WordPress site.
This made me see the dashboard again!! The plugin appears as deactivated and it can be activated again and set in the dashboard. But to keep things clean I added more steps:
5. Rename back the plugin folder to its original name, that is from “remove-dashboard-access-for-non-admins-REMOVED” to “remove-dashboard-access-for-non-admins”.
6. Then the plugin gets deactivated again, you just need to login again to worpress, and activate it from the Dashboard. You can then set it as normally.
I prefer to keep the folder with its original name to prevent future issues, as I already noticed that with the name changed some options (Activate, Delete) didn’t appear in the plugins list.
But all the credits for Fitshase / p3000 who found this solution!