s4pphicfelines Have you removed or renamed the Sims 3 folder in Documents > Electronic Arts yet? If not, please do so now. This would remove, but not delete, your saves and other user data, which is part of the point of the test.
If that doesn't or didn't help, try playing in a new admin Windows account. Make it local, as in, don't link it to your Microsoft account or any email address (you can skip that step), just to be thorough. If that alone doesn't work, do another clean uninstall and reinstall using that account rather than your main one.
Your saves and other user data won't be available in the new account, but that can be addressed later.