Because the Light-on Shoes Are Not USB Interface, It Is a Battery of the Sole That Can Store Electricity and Light up. Sometimes It Will Not Light up over Time, it Is Normal If One Is Bright and One Is Not Bright Or One Is Bright and the Other Is Dark. If There Are Light Problems, Such as Different Light and Shade on the Left and Right, One Light on the Left and Right Will Be Bright and the Other Will Not Be Bright, and the Color Is Uneven. We Do Not Treat Quality Problems Carefully!