Because you locked your topic too quick:It might also be your firewall if you have one. I've had instances where my firewall silently blocked game connections.If you have a firewall, try turning it off or set Blockland to be a trusted connection.
This isn't my router, it's my overprotective parents, and they already told me no on port forwarding.
There not going to listen to that.
Something you can try is to restart your router by unplugging it, waiting 10 seconds, and plugging it back in. Then start your BL server. (UPnP should also be enabled on the server - there's no reason to turn it off)