The latest stable version of BungeeGuard isn't updated to fix Spigot compatibility when there is a commit that already fixed this in the development build. That commit is f1e1e9c. This should be fixed as soon as possible as people might think the latest stable release works fine when they haven't tested that it doesn't. You can literally bypass the plugin because of this issue. Tested on Minecraft Spigot 1.20.4 if that is any use.
The latest stable version of BungeeGuard isn't updated to fix Spigot compatibility when there is a commit that already fixed this in the development build. That commit is f1e1e9c. This should be fixed as soon as possible as people might think the latest stable release works fine when they haven't tested that it doesn't. You can literally bypass the plugin because of this issue. Tested on Minecraft Spigot 1.20.4 if that is any use.