Hi guys, I would like a little help to figure out the right way to set this command with unbound-control

I'm trying to add a local-zone as

unbound-control local_zones "2mdn.net" always_nxdomain
unbound-control local_zones 2mdn.net always_nxdomain
unbound-control "local_zones 2mdn.net always_nxdomain"

According to the unbound-control -h this seems like the right syntax, but when I hit the enter, the console leaves me hanging, and nothing seems to happens before i hit CTRL + C

I'm running on Ubuntu 19.04 with Unbound 1.9.4
Compiled with as written here https://gitlab.com/rpz-zones/toolbox/issues/18#configure-options

Could someone please explain whats wrong with the syntax or ? and maybe give me an example of the right syntax for this example.

PS: This could also be a good example to add to the documentation 😃