Lava and water issues.

So after John had placed lava in my claim and my system was working, I warped out of the area for a bit, and when I came back both my water and lava had disappeared from my claim…

The lava and water were placed within the chunks covered by a world anchor.

If anyone has any ideas how to stop this it would be appreciated.

Water and lava should be saved within a chunk once placed. I think someone just stole the water and lava or the server had to roll-back.