The most likely cause is a fault with the image sensor or related still-image capture circuitry. Since the issue appears in still photos at different resolutions, but not in video, it points to a hardware problem rather than a setting you can fix in-camera.

For a compact camera like the DSC-W830, repair is usually not economical. The cost of diagnosis and repair often exceeds the value of the camera, so replacement is typically the practical option.

Before replacing it, you could do a basic check: reset the camera settings, try a different memory card, and confirm the problem appears in multiple images. But if the lines and ghosting persist, it’s most likely a sensor-related failure and not worth repairing.