This happens when you're automatically IPbanned by BlockNet for reconnecting to a single server too quickly. On shared nodes this is usually passed out of Blockland and onto the firewall preventing any further connections. I created this system to specifically prevent the Blockland specific dos attack that was produced by spamming massive amounts of torque connection requests, which would overload the Blockland application much more easily than it would affect the network (Gyt-whatever his name is had this issue on a number of occasions which prompted me to develop this, since BlockNet's network can tolerate most normal packet floods this attack was the only thing that could really make an impact on the server).
Anyways, the fact that you can still connect and are getting that error means that the torque-side code is being run on a server that isn't one of the shared BlockNet nodes. The ban list is stored in a global variable and therefore would be reset after the server restarts. If you want to contact the host to let you through, you can ask them to run deleteVariables("$antiSpam*"); to unblock you without a restart.
Also this is all under the assumption that this is my code producing this error code, it's possible that a different mod is doing it. Though I think that would be an unlikely coincidence.