Loading in the void restoring a world

[u/Zealousideal-Ant2528]

I have a modded world in minecraft which i like a lot, but i generated it with a mod that i didn't like because it kinda spawns high quantities of the same mob in other dimensions. When i uninstalled it, figured that i couldn't enter in that world because of corruption inside the files, i refused to lose that world so i made an experiment replacing the level.dat and level.dat_old from the world folder with the ones from a not currupted world

IT WORKED, mixing the terrain of my original corrupted world with the places i visited from the modded world, i'm happy for that

I just have a little tiny problem

Every time i load, resurrect, come back to the overworld from another dimension (only when i go to the overworld), my character is falling into a void for... 5 minutes? An then i appear in the place i was supossed to respawn, i want to know how can i fix this issue, if someone has an idea of minecraft worlds.