All my entities dissapeared

So i was playing on my minecraft World which was created in somewhere 1.16 and now i joined onto the World with my friend and i realized that all entities dissapeared the entities that dissapeared were sheep,chicken,armor stands and villagers  and it happened once i enabled multiplayer in the Settings

 

This never happened to me before so i reporter ut because villagers and armor stands despawning was weird

 

Thank you for your time