@Mertsho Does this happen if you launch Sims 4 through Origin? You can download an Origin installer from here:
https://answers.ea.com/t5/Origin-Client-Web-Technical/Downloading-and-installing-Origin-Windows-and-Mac/m-p/11915666
@gwyncanileave Is your computer actually trying to run the Legacy Edition, or is the problem that the LE files keep downloading? Origin and the EA App will both try to download any missing Sims 4 content you own, often even when you've specifically declined to install it, but that doesn't mean that the LE is in fact running. The question is whether the game launches in 64-bit or not.
If the LE is in fact running, try installing Origin (link above) and repairing the game, then switching to 64-bit: open your game library, right-click on the Sims 4 icon, select Game Properties > Advanced Launch Options, and choose 64-bit from the dropdown menu. If you don't see that as an option, please let me know. And in that case, you may need to set additional exceptions in your antivirus: the most common cause of this issue is that an antivirus has quarantined TS4_x64.exe, making Origin or the EA App think the system can't run the 64-bit .exe at all.
