Adding device tree overlay fail with libfdt fdt_check_header(): FDT_ERR_BADMAGIC error


I am trying to apply manually a device tree overlay (dtoverlay=vc4-kms-v3d.dtbo) in u-boot for my rpi4-b but i have this error: libfdt fdt_check_header(): FDT_ERR_BADMAGIC
. Usually i would use dtoverlay=dtoverlay=vc4-kms-v3d in my config.txt but somehow this does not work.

When I first type the u-boot command:
fdt addr
Nothing is printed, so i type all these commands:

 setenv fdtov_addr 2F0B2F00
 load mmc 0:1 ${fdt_addr} bcm2711-rpi-4-b.dtb
 load mmc 0:1 ${fdtov_addr} overlays/vc4-kms-v3d.dtbo
 fdt addr $fdt_addr
 fdt resize 8192
 fdt apply $fdtov_addr

But as I said previously i end up with the error: libfdt fdt_check_header(): FDT_ERR_BADMAGIC

I have checked that 0001-rpi-always-set-fdt_addr-with-firmware-provided-FDT-address.patch is indeed applied.

Note that environment variable are from meta-mender/meta-mender-core/recipes-bsp/u-boot/patches/0002-Generic-boot-code-for-Mender.patch

Any help is appreciated.
Thank you