I don't know if this will work and I can't test because I don't have your board.
From a different OS same error:
https://my-take-on.tech/2021/05/07/fix-docker-cgroup-errors-after-systemd-248-update/
The write-up indicates that might only affect old docker containers, so the possible fix below may only work for those containers.
To do the same thing in Armbian:
In /boot/armbianEnv.txt add a line (or if extraargs already exists add an extra argument separated by a comma)
extraargs="systemd.unified_cgroup_hierarchy=0"
