It broke my admin dashboard access

No matter what I do, on both of my websites, as soon as the plugin is activated, I completely lose access to my admin dashboard and it displays a “127.0.0.1 access denied” page. Please help me. I had to deactivate the plugin from my FTP server, but even if I uninstall and reinstall it completely, the All-In-One Security (AIOS) – Security and Firewall plugin will break my site as soon as it’s activated. It’s unusable, and I don’t even understand why.