Thinking about this, even though you reinstalled windows your pc would remember your previous settings by downloading them off the cloud, hence why it’s the same. Go start, (right click?) then device manager, find the mouse, open it and uninstall it, make sure it does not reinstall itself, it might reappear, if it does look in settings and see if you can do it there, then shut down and restart, it should auto detect the mouse and reinstall it, as you won’t have the mouse hold the power button and it should force a shut down.