I'm having a weird glitch with my Iron Golem farm. Specifically, there's one Iron Golem that seemingly can't be killed. It just won't burn and die. Sword have no effect, either. If I turn off the water flow it will burn, but not take damage (it doesn't flash red and flail about). Sometimes it disappears, only to reappear shortly afterwards. All other Iron Golems act like normal. I'm guessing it isn't really there, and it is some sort of glitch. The question is: how do I get rid of it?