Missing chunks

There is a huge area of around 10 chunks that's missing from my world and it's quite near my base. There used to be a pillager outpost in that area, and I have used third-party apps to edit the world (deleting chunks in that area to regenerate the outpost as I would trigger raids on purpose to farm emeralds and totems). The chunks always regenerated after I reloaded the world, but this time it's just void.