I only have 1 precious stone which is a sponge block. Players have

I only have 1 precious stone block in my config which is a sponge. i've had your plugin since roughly December 2012 and never had a problem with it.

Recently over the past few months, players have reported their sponges simply disappear, and these missing blocks have no LogBlock history, and the protection region disappears too. I keep the plugin up to date, but we keep getting reports about it.

Any idea why?