Help with relaying configuration for ipv6

I’m on an ISP that supports ipv6, but doesn’t do prefix delegation. So in order to get ipv6 to work, I have to use the relaying configuration mentioned here: Looks simple enough, but when I configure it, I can ping ipv6 hosts from the router, but not from any of the clients of the router. The clients are getting valid public ipv6 addresses though. Would appreciate any help!