Every time I load up the game all of my households and townies are gone

When I’ve had this issue before, I had to delete the game and reinstall it, if that still hadn’t work, I would assume that one of the expansion packs either has a bug or is making the system crash. If this is being played on an older computer, it may that your computer doesn’t have enough space or your software is having a hard time processing how many Sims and/or items you have in your game. May have to get an updated computer, see if any major expansions are having problems Via EA website.