Animals despawning despite being named (+ villager)

I took a break from Minecraft for about 4 days and came back today just to see most of my pets have vanished along with a villager that I had brought to where I live in the game so that I could trade them dyes. Some of my pets were named the only exception being the tropical fish I had in a large aquarium I built, yet they all, including the pets that were named, were gone. I thought maybe it was me so I closed the game and reopen it, but they were still gone