With a free IPv64.net account you can manage some DynDNS subdomains on your own. The service is free of charge and optimized for IPv4 and IPv6 connections.
You already have an account at IPv64? Then you can quickly log in here with your credentials.
Create a free IPv64 account here. With this account you can use all the services of IPv64.
You forgot your password again? It will cost you a small donation for these services.