Reinstall grub

Startup system with Debian Live USB key.

Prepare envirnoment to chroot

Mount system (here with boot included)

mount /dev/nvme1n1p2 /mnt # with /boot included in root
mount -t sysfs /sys /mnt/sys
mount -t proc /proc /mnt/proc
mount -o bind /dev /mnt/dev

Mount efi requirements

mount /dev/nvme1n1p1 /mnt/boot/efi  # efi
mount -t efivarfs none /mnt/sys/firmware/efi/efivars

When environment is ready

chroot /mnt

Check the NVRAM

efibootmgr --verbose | grep debian

Correct result (HD after debian is important)

Boot0001* debian	HD(1,GPT,b57757cd-9568-4135-a033-c7e6af81947d,0x800,0x100000)/File(\EFI\debian\shimx64.efi)