@esmesfunkeyass Are you trying to install to the same location where Sims 4 is already installed? By default, it would have been this when you used Origin:
C:\Program Files (x86)\Origin Games\
If the EA App is trying to install elsewhere, try choosing this location instead. Cancel the current download, clear the EA App's cache:
https://help.ea.com/en-us/help/faq/clear-cache-to-fix-problems-with-your-games/
Restart your computer, and when you try again to download Sims 4, pick the location where it's already installed. The App may simply verify the files' presence and finalize the installation process.
If that doesn't help, repeat the above, except this time, create a new folder where you want Sims 4 installed. The folder should be on the root level of the drive of your choice, for example C:\Games is fine, but not C:\Program Files\Games. You can move the existing Sims 4 program files into this new folder, as in, drag and drop the entire "The Sims 4" folder. And you probably know this, but just in case: this is about the folder that contains the game's program files, NOT the user folder in Documents > Electronic Arts.
If that doesn't help either, you'll need to manually uninstall the game and the EA App. For Sims 4:
- Put aside your Sims 4 folder in Documents\Electronic Arts and rename it to something that doesn't include the words "Sims 4."
- Download Revo Uninstaller (the free version is fine) from here.
- Launch Revo, select Sims 4 from the list, and click Uninstall.
- Cancel the system restore point; you don't need it.
- Once the game is uninstalled, select "Moderate" under "scanning modes," and click Scan.
- Review the list, in case there's something you want to save; otherwise, click Select All, and then Delete.
- Close Revo, and restart your computer.
For the EA App:
- Launch Revo, select the App, and click Uninstall.
- Cancel the system restore point.
- The EA App may open a window. Click Uninstall, then in the Revo window, click Moderate under Scanning modes, and click Scan.
- Revo will present a list of registry entries. Click Select All, then Delete: you don't need or want to preserve these entries.
- For the leftover files and folders, click Select All, review the list and deselect anything you'd like to keep (this is unlikely, but it's worth checking), click Delete, and you're done.
- Close Revo, and restart your computer.
Install the EA App, then create a new folder into which you'll install Sims 4. The folder should be on the root level of the drive of your choice, for example C:\Games is fine, but not C:\Program Files\Games.