So I was Pvping and found that shields will automatically block when you successfully block one attack. This could be server-side perhaps, it wasn't the most professional or lag free server out there. And this doesn't happen in PVE in singleplayer. Didn't try multiplayer PVE. I experienced it on another PVP server though too. Also, even when the axe thing disables my shield I can still autoblock after the first block.