just update minecraft after seeing notice . I just wanted to play woth my friends but the when i relog to my world its not my world anymore instead it was like and old world meanwhile my own world already had a buildings.

I logged on in my minecraft world for a check up like if my world still there or not yes it is still there then after updating my world called "learner" vanished. After that i try to turn on mc multiplayer and i cant turn it on. Plus this situation already happen 2 times . I logged on the wrong server. Theres a massive mushroom brokes villagers who already turn in to zombie. And now i cant logged on my real world