Here you can find how to solve error code 529 in The Sims 4.
While saving your progress in The Sims 4 you’ll get a message saying the sims 4 failed to save. The error code starts with 529 followed by a long series of numbers. These numbers can be different in your own game.
The game failed to save. Error Code: 529:7965179579417474670:17210182255063712811
This problem usually can be solved by letting your Sim go to another lot. In case that doesn’t help, you can temporarely evict the household or let them move out. If all goes well you should be able to save again.
1. Travel to another lot and try to save there.
2. Evict the household using “Manage Worlds” and then move them back in.
3. Let your household move out to another lot.