Infinite save screen, deletes previous save files upon "crash"

Product: The Sims 4
Platform:PC
Which language are you playing the game in? English
How often does the bug occur? Often (50% - 99%)
What is your current game version number? 1.110.294.1020
What expansions, game packs, and stuff packs do you have installed? All packs except the lovestruck expansion pack and a couple of kits. This category should be a drop down menu.
Steps: How can we find the bug ourselves? Play in build mode or CAS for an extended period of time. So functionally those two branches of the game are broken if you are creating a new build or sim.
What happens when the bug occurs? gets glitchy > infinite save screen > cannot end task for program > reboot computer > game deletes all SAVE FILES for roughly the hour or more before the crash occurs
What do you expect to see? I should be able to use CAS and BB without it corrupting the file and crashing the game.
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? Yes
Please describe the patch or change you made. The reaper events is when this started happening, but after the expansion pack for life and death it got worse.

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the issue is happening now every single time I play. It crashes.. I open it up again and try to redo the lost progress and it crashes again. On repeat. The crashes happen after playing for 30-60 minutes in CAS or BB. No matter how many times you save, all of it will be lost.  

You will first notice that things aren't working normally, but you can still build or create the outfits (despite some functions no longer working). When you save the game it goes into an infinite save screen. Once this happens you cannot open your (ctrl/alt/del) "end task" window because the sims screen continues to overlay the entire screen and cannot be minimized. There is nothing left to do but forcefully power down the PC. Then upon restarting the computer and opening the game, several hours and multiple SAVES worth of data are just GONE. Literally hours of gameplay, building, or cas efforts GONE despite saving many times prior to the crash. I will have the sim or the build uploaded on the sims account library yet the save file for the GAME will have deleted all of that progress from the save file. Sometimes it has fully deleted the sim or the build entirely. This is insane. Please understand what I am saying.. The game deletes your save data but the online library retains anything uploaded to it. 

If you then try to place the lot back into your game.. several items are are CLEARLY VISIBLE in the library file will be removed from the lot. That's a whole other complaint that I need to file. My point is that clearly the saves are not working despite the data being able to upload to your library.

FYI: This DOESN'T log as a crash because you are forced to reboot the PC. I wish I could end the program, but the option is inaccessible with the screen overlay issue... WHICH.. I think is another report that I need to file as well.  

I have not had any CC since before lovestruck pack was released. 

side note: WHEN I NOTICE THIS HAPPENING I can exit CAS or BB. Playing the game seems normal at first, but the game still will not do tasks properly. If you save the game, then crash will cement itself. It is basically already functionally frozen. What makes this so hard is that I suspect that the crash started hours before the save that freezes the game. Why else does it delete all my saves leading up to the implosion event...?