Use the Rockchip SD Firmware Tool . Choose your card, click "Upgrade," and select your firmware file.
Simply copying the .img file to an SD card won't work; it must be flashed onto the card. Insert the SD card into your PC. Open your Card Maker tool as an administrator. Select your SD card drive. Check the option (if available). Mxq Pro 4k Firmware 7.1 2 Download Sd Card