Mouse settings are normally in the Control Panel, mouse, or touchpad or whatever is used to set the device up. It also may be in the hidden icons on the Taskbar.
Since Touchpads have settings related to different parts of the touchable area, you may have some setting related to an edge or corner.
But if you can't find a setting that helps, you may need to reinstall the driver.
We did see a situation once what the focus would change on a system without a window being selected. That seemed to be related to a specific type of flash drive being plugged into the system.