I had limited success with "grub-reboot 2", but the following worked fine for me on an AWS EC2 running Ubuntu 20.04.2
sudo grub-reboot "Advanced options for Ubuntu>Ubuntu, with Linux 5.13.0-1025-aws"
I had limited success with "grub-reboot 2", but the following worked fine for me on an AWS EC2 running Ubuntu 20.04.2
sudo grub-reboot "Advanced options for Ubuntu>Ubuntu, with Linux 5.13.0-1025-aws"