Animals won't spawn in my world

Like the title says, animals wont spawn in my world and I'm not entirely sure why.

Recently I moved my world that I've had since Xbox 360 from bedrock to java, and all my mobs got wiped. I was expecting my mobs to disappear but even the animals that are supposed to spawn have disappeared. I have all the correct spawning conditions and they haven't been over hunted, I went looking for animals and didn't find a single one for almost 2000 blocks, this is even after stopping and waiting for animals to spawn, the only peaceful mobs I've had spawn in my area is One wandering trader and 2 llamas. Hostile mobs are spawning just fine too which is why I'm so confused.
Villages that I found in this 2000 block radius were empty when I know I have not been to them since I reset all the chunks outside my main map that I started with on Xbox 360.
I seen another post similar to my situation while looking for a fix - that I did not find - but that person had animals spawning in their area. So my question is, how do I fix my animals spawning??

side note - I've also noticed about 200 to 300 blocks out in each direction from my original 360 borders, chunks are missing, all the way down to bedrock and it only gets worse the further I go out. oh and for whatever reason there's rain in the end that doesn't seem to hurt the endermen but I can use riptide in so it's def real.