The problem was because the boot/efi partition was mounted as read-only. After remounting it as read-write. I have got the same error like in the https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1282375
The problem was because the boot/efi partition was mounted as read-only. After remounting it as read-write. I have got the same error like in the https:/ /bugs.launchpad .net/ubuntu/ +source/ grub2/+ bug/1282375