Villagers, golems, and fenced in animals keep vanishing.

I build next to a village and as of last week, the world I was on (and two other new test worlds I made) have had ALL villagers, iron golems in that village, and any fenced animas near that village, completely vanish. It has happened if I exit the game and come back, it has happened while I’m standing in the village. I cannot figure out what happened all the sudden to cause this.