'System Error' when placing lot

I have exactly the same problem with the “system error” message since the January 2026 update.

I had created a rental property lot and saved it in my gallery to install it in a new save file. However, it was impossible to install it. It is a 50x50 lot with platforms and terrain modifications.

So I tried changing the lot type to residential, saving it again in the gallery, and installing it again in another save file, but I still get the same error message. I also tried installing it from the worlds, and the “construction in progress” loading time is displayed, but once it's finished, the lot is empty.

I then tried installing other similar plots and had no problems. However, these were plots that I had created and saved in my library before the January 2026 update.