Thank you for contacting us regarding this issue, @martin Thomas
DNForum has systems in place to prevent malicious users from joining. Some examples of these safeguards would be for allowing the use of any VPN or ToR exit point as we believe in a user's right to privacy, though having automation take out bad actors that may be using the same internet identity, or IP address, rather.
As you reached out to contact us, it's obvious to me that you are a sincere user and don't fall into any of the categories of users that we try to thwart from joining the forum in the protection of our members. As such, the ban has been lifted and you may now freely participate at the level of what a new member in the free tier can.
If you have any other problems, please do not hesitate to reach out to us again.