Updating the IPv6

Hi all. I have been unable to make ddclient update my IPv6 on this site. Has anyone ever made it?

Was working fine for me one year ago using ddclient on OpenWRT*1.
What’s your actual setting?

*1 At the moment I don’t have OpenWRT so a Raspberrry Pi 3+ is in charge, but I can’t tell if it works now because my network’s IPv6 didn’t change for months already.

I am using Raspberry Pi OS (formerly known as Raspbian). They say to use this in ddclient


I used it but it but when i go to the site and look at this subdomain there is no IPv6 there.