You definitely don't want to block that IP because it's yourself.
If you're seeing 127.0.0.1 appear in your live traffic often, then you need to change the setting on the Wordfence options page titled "how does wordfence get IP's" to something appropriate for your site.
You can try "use PHP's built in REMOTE_ADDR" which is what commonly works for most people with this issue.
Regards,
Mark.