I have this issue since the Adventure Awaits EP release. I installed it and I owned every single DLC and they are all installed. No mods and game version up to date.
Often I play and my sims keep forgetting commands, especially when talking to multiples people, but not only that, also I ask them to take a shower and its immediately cancelled. Its now on a lot of different interactions. In addition, interaction involving toddlers were also cancelling and having sims standing in front of each other, waiting to start the interaction but nothing happen after hours in game. I had this issue as well when my kid tried to mount a horse. Sometime I will enter the cheat code ''testingcheats on'' and reset my sim, only to see my sims doing a T pose and being forever frozen in T pose... then I have to reload the lot or the game to fix it. Sometime they will reset and I tried the interaction again, but it keep not working at all...
I have disabled the Memory boost, because I want my graphic maxed out with antialising and unfortunately at the moment when you switch on the memory boost, the antialising seems to be turned off and its ugly, plus it does not provide any better frame rate for me...