Nelson R

I doubt that this is the same case, but I had the same error on an orangepi pc so for future reference I comment here.
I had upgraded to buster from strech but it seems that the command lsb_release did not work and probably armian.config could not choose the appropriate debian release. Then the list (/etc/apt/sources.list.d/armbian.list) contained no release info, and I was getting the same error. Just adding the release solved the issue.
 
root@orangepipc:~# cat /etc/apt/sources.list.d/armbian.list #deb http://apt.armbian.com main -utils deb http://apt.armbian.com buster main buster-utils  

Just a hint: building inside virtual machine is recommended for security reasons since script runs with superuser rights. In case of some nasty bug (ours or from external sources), your host machine can be wiped or crippled. If dedicated virtual machine is wiped is usually not a big issue.