can you be more specific about the command?
trying this out:
mircea@tarhon:~/nxp/imx-yocto-bsp6/newbuild/tmp/deploy/images/imx8qmmek$ sudo uuu -b sd u-boot.bin
uuu (Universal Update Utility) for nxp imx chips -- libuuu_1.5.21-0-g1f42172
Success 0 Failure 1
1:3 1/ 1 [HID(W):LIBUSB_ERROR_IO ] SDPS: boot -f u-boot.bin