Error Code 134:54350669 - Unable to load family

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? 1.58.69.1010
What expansions, game packs, and stuff packs do you have installed? All except Moschino Stuff
Steps: How can we find the bug ourselves? Try to load saved game
What happens when the bug occurs? Error comes up saying "The game failed to load. Error code: 134:54350669:466a9f21. It is recommended you relaunch the game.
What do you expect to see? To be able to launch a save.
Have you installed any customization with the game, e.g. Custom Content or Mods? Not now. I've removed them.
Did this issue appear after a specific patch or change you made to your system? No

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Before this error occurred I was having a bug with Sims at University being stuck as always "In Class" and unable to send my Sim to class or open inventory. I exited the game and when I got back in I am unable to load the save of this family. I exited the game and got back in, removed custom content (never had script mods), tried exiting and entering again. Now the household has an exclamation mark symbol in manage worlds and the above error keeps coming up when I try to load.