Hello, I am having a similar issue. It began after the September 18th, 2025 patch (Version 1.118.242.1030). My sims will get stuck performing an interaction for an extremely long time (3-4 in-game hours). In addition, any other sim on the lot who isn't performing an action will be stuck standing still, or doing an animation if they were performing an action. I.e., my sim was painting, she gets stuck performing one painting animation along with any other sim on the lot, the painting won't progress and her task bar completion bar won't progress but once the lag stops the completion bar will go to the end quickly and the painting will become finished. I noticed it happens 100% of the time when my sim is holding a class at her small business, but sometimes happens at other times as well.
The lag will not stop even if I reset the sim. Clicking on anything while the game is desynced will be extremely delayed, i.e. if I click on another sim it will take 2-3 seconds for the wheel to appear when it normally appears almost immediately. If I turn on speed 3 during the desync the time will start skipping forwards and backwards erratically.
I tried removing all mods and cc, deleting EA app and Sims 4 cache files, repairing the game (without mods installed), creating a new save, to no avail. The same issue occurs in new saves periodically and almost immediately if I start running a lecture using the hobby board from Businesses and Hobbies.
General info: I play on Windows PC, this issue was replicated with mods and cc removed, game repaired (after mod removal), and caches deleted (after mod removal).
