Disappearence of villagers

Hello, I don't understand why for no reason the villagers of one of my favorite villages disappeared, but not only the villagers but all my animals. This happened twice. It's bad to invest time and money in a game and be sabotaged without knowing the real reason. It wasn't zombie attack or any other external attack, it was missing due to game failure. Hope this issue is resolved. I'll try to recover the village one more time, if it disappears I want a good justification for not having to file lawsuits if that's possible. I thank the attention.