A. Check whether the fire button is struck. B. Check whether the pod is in good condition. C. Clean up electrodes and make sure the pod is installed in place. D. When the battery is lower, the device can’t work. Please charge the battery to try again. E. If there is a short circuit, low battery or coil with poor connection,etc, please refer to the user manual. F. The internal components may have been damaged (such as dropping, juice into the device).