Well I have a zombie spawner near my villager housing and whenever I try and cure a zombie villager that was from the zombie spawner it would just lag my xbox and return to home screen where I would have to log in again and I tried multiple times to fix it by switching to creative on a copy of the world and doing it on there but still nothing I also went on creative again on another copy to go as far away as possible(a few thousand blocks) still lagged me out! I have also done it tons of times but now suddenly it stopped curing the villager, and also all my other villagers that were cured are from the same zombie spawner.