In a realm that me and my friends share we have made many mob farms, however whenever we use a mob like a zombie or a pacified pillager they always seem to despawn. We have tried name tagging them, always having the chunk loaded but nothing seems to work. This issue has happened many times and is a big problem as we can make no farms. Villagers have also been respawned from our world even though they had a name tag and we traded with them