So i was in sg arena 2 and all of the sudden i could not move more than a few blocks the video will explain everything.
This is nocheat stopping you from moving. It happens when you glitch out on a block sometimes, the best solution is to stand still for a minute or two (Yes, I know you can die when you stand still)
If you jump and move eventually goes away. See how when you jumped it changed just keep hopping and voila