@fatherprax no, that's not my problem. I don't use DHCPv6 either. I use RA. My WAN interface requests a 56 prefix instead of just 1 address. and my LAN interfaces are just set to 'track interface' and they get a bunch to give out to their devices.
You can go to https://ifconfig.co/
or do a
curl -6 https://ifconfig.co/
That should work on your machine, if it doesn't, then you don't have a valid ipv6