We have pushed a new kernel (version 5.10.110-11) that contains a related fix. Can you try upgrade the kernel on your eMMC and run again?
To do so, first, boot from microSD with eMMC connected. Assuming the eMMC is listed under /dev/mmcblkX (substitute X with the real device number):
sudo mount /dev/mmcblkXp2 /mnt
cd /mnt
sudo wget https://github.com/radxa-pkg/linux-rockchip/releases/download/5.10.110-11/linux-image-5.10.110-11-rockchip_5.10.110-11-8c4e8d205_arm64.deb
sudo wget https://github.com/radxa-pkg/linux-rockchip/releases/download/5.10.110-11/linux-headers-5.10.110-11-rockchip_5.10.110-11-8c4e8d205_arm64.deb
sudo apt update
sudo apt install -y systemd-container
sudo systemd-nspawn
dpkg -i /linux*.deb
exit
sudo poweroff
You can then remove the microSD card and try booting from eMMC again.