UEFI messages on startup

Hi,

I see these messages on startup with a rpi_4 - what can we do about this? It happens on every boot.

** File not found ubootefi.var ** Failed to load EFI variables ** Unable to write file ubootefi.var ** Failed to persist EFI variables ** Unable to write file ubootefi.var ** Failed to persist EFI variables ** Unable to write file ubootefi.var ** Failed to persist EFI variables ** Unable to write file ubootefi.var ** Failed to persist EFI variables ** Unable to write file ubootefi.var ** Failed to persist EFI variables ** Booting bootflow '<NULL>' with efi_mgr Loading Boot0000 'mmc 0' failed Loading Boot0001 'usb 0' failed EFI boot manager: Cannot load any image

Regards, Simon