Sims won't complete assigned actions

Hey,

My game was working fine yesterday, but today my sims appear to have become disobedient. I am currently playing 2 sims at university, but when I assign them tasks they will start them but after a few sim minutes/hours (depending on activity) the action will just cancel itself.

They aren't being cancelled by an alternative action, it simply just stops. I've noticed this with sleeping, writing books/term papers on the computer, eating, showering and exercising. Sometimes I can work around this by lining up multiple of the same action to keep them working, but it isn't working with sleeping so am having to use cheats.

I have tried to resolve this by resetting the sims, resetting the objects, restarting the game and also repairing the game through Origin. I have also changed the settings to disable sim autonomy, but it hasn't stopped them having autonomy.

I have also noticed the random appearance of that annoying ball of clay repeatedly in my sims inventory. I have never bought one, or picked one up, but they'll randomly start using it. I'll check their inventory and 3-5 of them have randomly generated (they were in their room working so hadn't picked any up on the lot). Not sure if it's related, but it's irritating.

I don't have any mods or CC. I own all packs except for Tiny Living and Moschino Stuff.

Edit:

I restarted my computer, went back into Origin and the game plus all packs had been uninstalled so I reinstalled them and continued my save game. The only positive is that my sims now sleep through the night, but they still won't eat or complete actions and their autonomy is still very much on despite changing the settings. The clay is also still persistent and frustrating. I have pretty much had enough of this bug filled game now 😞