Sims 4 suddenly became slow!

Could you make sure The Sims 4 is running on your GeForce card?
sims4.crinrict.com/en/2014/09/graphics-cardintel-chip-dual-systems/

I have done this a couple of times, I'm not %100 sure I'm using it in game but it's already set like that. Do you think I'm using the Intel one, cause I sometimes feel like it? I open CPUID while in-game and Intel HD's temperature changes and NVIDIA stays the same.

Could be, do you have both the 32-bit and 64-bit set up for the GeForce card?

You could also test if the game runs better without CC and a clean folder. You can do that by renaming The Sims 4 folder in Documents. The game will create a new, clean one, test the game on that. If it runs better we know it has to do with something in the old folder. If it doesn't run better you can rename the old folder back to the original name.

I don't know if I have 32 bit and 64 bit ☹️ My pc is 64 bit, that's all I know. Also, removing cc, tray files and saves doesn't make a change ☹️

If you have a look at the link I posted you can read about adding the 64 bit and 32-bit version of the game in your GeForce settings. You should also be able to see over there if they are added.

I actually selected 64 bit in nvidia control pannel and i tried to open it but I'm getting an error for core/activation64.dll file missing. But when I look inside the core folder there is the activation64.dll file. So it didn't work ☹️

Did you select TS4_64.exe?

The activation64.dll is a Windows issue which you could fix by installing these packages:
https://www.microsoft.com/en-us/download/details.aspx?id=40784

I have downloaded them but it doesn't work. 

-----Worked when I opened the 64 bit version in the Bin folder but doesn't work when I copy it to desktop.

-----Yeah opens but it's not any better. I have run out of options and ideas honestly ☹️

Wait, why are you copying it to the desktop? Did you read what you had to do on the link I sent?

You'll have to add the 64 bit version in the Nvidia Control Panel.

Maybe it helps if I post the steps here?

1. Right-click on your desktop and choose Nvidia Control Panel
2. Click on Manage 3D settings.
3. Click on the Program Settings tab if its not already selected.
4. Step 1: Select TS4.exe (for 32 bit version) or TS4_64.exe (for 64 bit version). Use the Add button to get it since it usually doesn’t show up in the drop-down list on its own. You find the file in programs(x86)\Origin_Games\thesims4\Game\Bin (Path may differ)
5. Step 2: Select High-Performance Nvidia Processor.
   
   (Source: https://sims4.crinrict.com/en/2014/09/graphics-cardintel-chip-dual-systems)

Yes I have done everything, nothing worked, I have contacted an EA advisor. They couldn't help it too. My case and files are sent to a different team. I have some weird things going on I guess. Thank you for your helps too, you have sent a lot of replies. Now I will wait for specialists to send me an email.