Game Data lost after windows update

@raitro  Your user data is located in Documents\Electronic Arts\The Sims 4.  If that folder is deleted or moved elsewhere, the game can't find it and creates a new one with no content.  It's possible, but unlikely, that a Windows update would delete the folder, and even more unlikely that three successive updates would all delete the folder.  What I would guess is happening is the folder is being uploaded to OneDrive, and since it's no longer in your local Documents folder, the game can't see it.

Please check your OneDrive's Documents folder for any folders labeled "The Sims 4."  If you see one, you can move it back to Documents\Electronic Arts on your hard drive, and the game will read your content again.

If you don't find anything in OneDrive, open a File Explorer window, type "config" without quotes in the search box, and look for any config files inside a Sims 4 folder.  Each user data folder will have exactly one config.log, which will have the date of the last time the game launched while using that folder.  So you'll know which one is new, and which one you were using immediately before the Windows update.  Again, you can move the whole Sims 4 folder back to Documents\Electronic Arts.

In the future, it's a good idea to back up your user data folder regularly, and especially before you let Windows update.  The best practice is to copy the folder to an external hard drive or USB stick, but you can also upload it to a free cloud storage service such as Google Drive or Dropbox.