Ensure you have access to a Linux-based toolset for the best results. Flash the Loader:
This isn't just another stock ROM. This article dives deep into what this firmware is, why you need it, how to install it, and where to find the legitimate exclusive version that won't brick your device. r29 mxq lp3 v23 firmware exclusive
While holding the button, plug the other end of the USB cable into the box (usually the USB-4 port). Flash via PC Open the Rockchip Batch Tool and import the firmware .img. Ensure you have access to a Linux-based toolset