Unnamed Minecraft Villagers despawned after the 1.16.100 update.

On a realm server I haven't played immediately after the update but once I joined and went down to trade with my villagers I noticed my three librarians had gone missing. The one that didnt go missing was one that was name tagged so I'm assuming that the fact that the other three librarians weren't name tagged must've been the reason they despawned after the update. (They were previously zombie villagers but they were healed.)