One possibility of this problem is the photosensitive element of your optical mouse, that is, the luminous part at the bottom of the mouse. At this time, you may need to replace the optical mouse again. Another possibility is where you put your mouse, especially the mouse pad. If the mouse is placed in an unsmooth place or the material of the mouse pad is not good, it will cause the problem that the mouse moves by itself. You can put the mouse on a dust-free or soft and smooth mouse pad.