World height changed

It wont let me put in beta version 1.17.30.23 The height of my known world was changed upwards by about 70 blocks. Newly generated areas are at normal height, but old areas are at cloud height. When I reach the edge of the old area there is a literal cliff plunging down. I don't think it's a corrupt save file as this affects any old saved world I open in Beta. Also all animals and villagers disappeared. I believe they remained at the old height and sffocated, except for 4 cats that were close enough to teleport to me. Also all items in containers disappeared, except for player inventory and contents of the ender chest. All hopper minecarts and boats also were gone, Nether and the end were not affected, but portals to the nether are one way only. Trying to return from the nether places you in bedrock. Breaking and rebuilding the portal did not fix this. New portals in newly generated aeas work fine. A Minor issue, the dragon skulls I had on a wall all changed to skeleton skulls, and the Illager banners I had hanging changed to black banners. This happened between logging off one night, everything seemed noemal, and when I logged in the next day I had the message about the new beta version, and found everthing this way.