First, please confirm that the device has been upgraded to the latest version. If the device is confirmed to be the newest version, the problem may be caused by the inverter and battery not being properly connected. Turn off the inverter, unplug all cables, separate the battery and inverter, re-stack them, and restart the inverter to see if the problem is resolved. If not, and spare inverters or batteries are available, please re-stack the inverter with the red light using a different battery pack or re-stack the new inverter with the original battery pack to identify the cause of the problem (inverter/battery pack).