[Plugin: Better WP Security] .htaccess BlackList and White List

Something very strange is going on.
I have included my IP address for the White List and including my son.,
And we both get put on the Blacklist a few hours later.
Why would this happen when we both have our IP addresses listed in the White List??

Need Help on how to resolve this issue please

http://wordpress.org/extend/plugins/better-wp-security/