Body Sliders gone in Base Game

Hello there!

Tried searching for an answer to my issue, but nothing fits exactly.

Sliders for body shape have disappeared for my sims. Yes, yes, I know, that's a problem others have mentioned. However, in this case, I am playing the base game, with no mods, cheats, or custom content, unless looking at the (but not using) "Stylised Looks" counts?

As others have noted, when this happens, presets also disappear and only tattoos and body hair is changeable.

It's also not going to be because of pregnancy either, since one is male in any case, and there's been no "trying for a baby".

It's not the only bug/glitch I have, but it's the most annoying; the others don't matter or can be worked around, such as the "Break up with (name)" want has never worked, but it's only 100 Satisfaction points and they aren't exactly hard to get, and the items that can't be repaired when they break (because you made them unbreakable?!?) is just a matter of buying a new one, not a serious problem.

I've also noticed that since these sliders disappeared, my sims can't get fat, no matter how much they eat and don't exercise (I'm not cruel, I was trying to trigger the sliders to reappear!). Not sure if they can't gain muscle, that's harder to notice since they were both fairly buff anyway.

I'm playing on PC via Steam.

TIA, EOP