stockrom R831K 11.A.13
Step 1: Copy the ROM .zip Natural Color on the machines to not unpack.
Step 2: Move the computer to the Recovery mode by off then power + Volume Down Press (backup device before performing.)
Step 3: Select the English language by tapping the touch screen.
Step 4: Choose Wipe Data and Cache to delete all data older rom.
Step 5: Select “Install from SD”
Step 6: Select the file you just copied to FW machine.
Step 7: Wait for the machine to automatically install and then Reboot the computer and enjoy the fruits