You have the file. Now follow this precise method to flash it.
Common firmware layout (typical embedded device) 40ms801amac2hg firmware top
If you cannot find a working build, consider compiling your own using or Amlogic Customization Tool (for AML variants). But for 90% of users, the builds listed in this article will restore smooth performance and modern app support. 40MS801AMAC2HG Firmware Top: The Ultimate Guide to Updates,