root@laptop:/root# update-initramfs -u -k all
update-initramfs: Generating /boot/initrd.img-5.4.0-37-generic
cryptsetup: ERROR: Couldn't resolve device rpool/ROOT/ubuntu_0ctpm6
cryptsetup: WARNING: Couldn't determine root device
I: The initramfs will attempt to resume from /dev/nvme0n1p2
I: (UUID=09c1daa8-a572-41b9-8655-c38ea7778723)
I: Set the RESUME variable to override this.
root@laptop:/root#
Change your /etc/default/grub GRUB_CMDLINE_LINUX_DEFAULT to point to your real partition