This is an old revision of the document!
Some images and OS distros still can use old boot-loaders blobs which not compatible with new hardware revisions v14.
Solution:
This can get after writing old images into internal eMMC storage for new board rev v14
In this situation easiest way is re-flash device by right image for restore it.
only for old revisions board v12
curl -OjkL https://github.com/khadas/khadas-uboot/releases/download/0.16.4/VIM3.u-boot.spi.bin spi_update < VIM3.u-boot.spi.bin kbi bootmode spi kbi poweroff