How to remove GRUB from Windows laptop (MS Surface Pro 3) – the 4x BootRec commands did not work

I have Windows 11 running on my MS SP3 laptop. I had Ubuntu also installed, but removed the partitions for it. The laptops DOES still boot, but I have to type “exit” at the GRUB screen – how can I just get rid of the GRUB screen at boot up?

I have booted to a Win11 installer on a flash drive and ran the 4x BootRec.exe commands, but they did not fix this:

BootRec /FixMbr
# "The operation completed successfully"
BootRec /FixBoot
# Access is denied
BootRec /ScanOs
# Total identified Windows installations: 0
BootRec /RebuildBCD
# Total identified Windows installations: 0

Any other ideas?