My sims get bad grades

Hey guys. I know the title of the topic sounds stupid, but here is what happens: my game works perfectly fine, but lately (not sure if it started after getting Tiny Living or not) my sims gets suspended from university because they keep getting Fs no matter what I do! They do their homeworks, go to classes where they takes notes or actively listens, submit outstanding term papers, all the presentations are excellent and still, they get Fs! It is super annoying, they get on probation, then suspended...it is like University expansion just broke LOL...I ca no longer get a degree for my sims. 

I googled this issue and discovered there are also a few people with this issue...but no solving. Do you have any idea if there is a way I can fix this?
I have to mention I am playing with this family for like an year now...this is like the 11th generation. Could this be the problem? Should I start all new?  Sounds silly, I know. Did this happen to anyone else? 

Please help! :-D thank you!

Mods?