inventory disappearing upon game launch

inventory disappears every time i load in minus a few items— any time i launch the game, my sims inventory (not everything but almost everything?) is completely wiped out. all of my sims in the household it happens to. the only things that end up staying are upgrade parts,  sheet music, and the camera. i have to keep re buying everything they usually carry in their inventory, most importantly their HOMEWORK is gone! it’s not the end of the world it’s simple to get homework and everything else BUT it ruins my plans of no cheating.  because then i am using “kaching” to get back the money they had to spend because the game glitched.