Pause & Inventory buttons stop working, blocks don't load all the way, and tamed animals disappear upon reloading world.

I'll be in my world far from the world spawn. I'll gather wood or wolves because I'm far away from these biomes. When heading back/towards, the game decides to not load blocks all the way, tamed animals (such as wolves, horses, etc.) disappear.  The ability to pause, open inventory, and switching items become disabled and do nothing. Closing the app fully and reopening world, also doesn't save all progress.