Please use this thread going forward: Neighboring Houses show as Default/Empty | EA Forums - 11903590
I had this problem only once with one lot: the lot became empty in the neighbourhood view, but had its content when entering to build/buy
It happened after bulldozing a lot, exiting without saving to the main menu, and then going back to the same save
I entered the lot, it had its content as if not saved, as it should have; only the neighbourhood view was corrupted
I read something in @crinrict's website, but I don't remember where, that some stuff can be "contagious" between saves
if you exited the game (TS4_x64.exe is not running in your task manager) and you still have the "scratch" folder inside your "saves" folder, try to delete it to see if the problem is resolved (do not delete this folder if the game is running or you'll have a corrupted save file)
also, try not to exit the game to the main menu. Always use Save As, not Save, and when changing the save file, exit the game so the scratch folder is deleted
Thanks for your tips ! I tired to observe what was created in the Save folder and that's right, even before loading a save, this scratch folder is generated with I guess the first save of your list, so yes, it's a good practice to be careful about that 🫣 (at least in my case it's deleted after closing the game, but I haven't seen what happens when it crashes.
I gave up and I'm planning to recreate my main save from scratch, but I really hope EA will look into that, or at least that we will be able to identify what causes those issues to avoid them 🥲
