Unable to exclude certain user role from accessing locked site

The plugin is great but I’m facing an issue. I want to locked site for non subscribers only. So, user with subscriber or author role should be able to access the site. I see that it is working for frontend but when the subscriber try going to /wp-admin or try to manage their profile, it won’t work. May I know why?

https://www.ads-software.com/plugins/maintenance/