I have the same issue on an Odroid M1. Also installed twice to make sure it wasn't the installation. I can access the container if I attach it to the host instead of the bridge, but since I'm going to be running multiple containers with the same internal ports, that is not a solution.
Output of armbianmonitor -u:
Collecting info and sending to paste.armbian.com, wait...
/usr/bin/armbianmonitor: line 976: iostat: command not found
https://paste.armbian.com/vuzemedifu