chunks load weird and make tall sharp edge hills

all my llamas despwanded and my 11 dogs also did when i leave beta and rejoin, my llamas had chests with my diamonds, enchanted books, obsidian, netherite tools and brewing materials because i can't find a good home, anyway... and i can't play minecraft anymore because if a make a change in that world like smelt something it crashes and deletes the tool i was using to smelt it, the fuel and the thing i was smelting.

mojang pls fix this cuz minecraft is MY LIFE