Server Software: Bukkit
Server Version: 1.12.2
BanManager Version: 7.0.4
config.txt

When I run the /bminfo command and tab a name, nothing comes up in-games, and this error message appears in the console.
error.txt

Please see #863

Ensure offlineAutoComplete is enabled in your config regarding the tab issue

This is enabled and I can tab other people's names. However, when I press enter to run the command, nothing shows up and the error appears in the console. I apologize as that might not have been clear at first.

The issue is caused by a wrongly formatted ip field. The issue I linked covers how to resolve it #863 (comment)