Realms crashing and reversing progress

My realms are disconnecting me and coming back several minutes, at first I thought it was my iron farm, because I had put 8 more villager in it, totaling 20 villager, I killed 8 villager and left 12, the same as it was before, when it didn't crash, but it didn't work, it crashed and came back several minutes again, I thought it was the end farm that was doing this, but I broke it and it keeps crashing.