Pregnant sim can't gain skill from skill books

Product: The Sims 4
Platform:PC
Which language are you playing the game in? English
How often does the bug occur? Every time (100%)
What is your current game version number? 1.62.67.1020
What expansions, game packs, and stuff packs do you have installed? As of april 2020 I have all the packs installed.
Steps: How can we find the bug ourselves? Get a sim pregnant and try to read a skill book.
What happens when the bug occurs? When a pregnant sim reads a skill book, that sim does not gain skill.
What do you expect to see? I expect to see the pregnant sim getting skill when reading skill books.
Have you installed any customization with the game, e.g. Custom Content or Mods? Never used.
Did this issue appear after a specific patch or change you made to your system? Neutral/Not Sure 

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I am currently doing the 100 baby challenge and basically got every skill maxed. I only need a few which I have been trying to get via books. For the longest time I couldn't figure out why I could not get any progress on the skills. The specific skills in question is herbalism and archaeology. 

As im doing the challenge I am constantly pregnant but I didn't think this was the problem until I had a full house and couldn't get pregnant for a while. I decided to try reading again just to let the time pass. The skill actually got progress! Naturally I was exciting thinking the bug was fixed but as soon as she got knocked up again, she didn't gain any progress when reading the skill books. I also tried all 3 tiers of the books so the problem is not that the books are too hard/easy.