If the P1 fails to download the firmware over 4G, it is often due to restrictive APN settings or network throttling by the telecom provider. Switch the device completely to a 2.4GHz Wi-Fi network and try the update process again. 3. MDM / Custom ROM Restrictions
Powering off a Sunmi P1 mid-flash can permanently brick the motherboard's memory chip. Sunmi P1 4g Firmware
: Navigate to Settings > System > System Update . If the P1 fails to download the firmware