when i try to join the world to load it it freezes and doesn't let me join, the world it just freezes

hi and i would like to talk about an bug which i would call in the beta better together when i try to join the world to load it it freezes and doesn't let me join the world, it just freezes and that was my fav world so could u help me. when i was building i fell in lava by accident and i left the game and now i cant join back and i did hard work on it and i dont have a backup. the green bar doesn't even load