So I changed it to blank and got NOTHING now for lan ipv6 other than linklocal

And file is now

interface em1 {
        send ia-na 0;   # request stateful address
        send ia-pd 0;   # request prefix delegation
request domain-name-servers;
request domain-name;
script "/var/etc/dhcp6c_wan_script.sh"; # we'd like some nameservers please
};
id-assoc na 0 { };
id-assoc pd 0 {
};

Again – changing it back to 0 and rebooting again.

So once I changed it to 0 before reboot when I look at status for lan I showed this again
IPv6 address 2001:558:6033:12c::1

edit: ok after setting back to 0 on lan interface and rebooting I am now getting
IPv6 address 2601:d:8b80:c0:250:56ff:fe00:2

Again -- this is working, but pretty shitting address for your gateway ;)  Why would it be such an address and not like 2601:d:8b80:bf::1 where it was before?  I would think the address should be 2601:d:8b80:c0::1

2001:558:6033:12c::1

where wan /128 is 2001:558:6033:12c:1477:7c9d:b69f:a3d3

Before when it was working my lan would be for example 2601:d:8b80:bf::1, this is the old address I had.  I thought comcast was using the 2601 for their /64

If I reboot then I don't show that ipv6 on the lan, but if I toggle none to tracking on the lan then the 2001 address shows up.

What can I do to help troubleshoot the issue?

edit:  If I look in var/etc/dhcp6c_wan.conf

interface em1 {
        send ia-na 0;   # request stateful address
        send ia-pd 0;   # request prefix delegation
request domain-name-servers;
request domain-name;
script "/var/etc/dhcp6c_wan_script.sh"; # we'd like some nameservers please
};
id-assoc na 0 { };
id-assoc pd 0 {
};

That id-assoc pd doesn't look right - should something be in there vs empty {}?

edit: ok rebooted again and now I get 2601:d:8b80:c0:250:56ff:fe00:2

As lan IPv6 address, and if I set one of my lan boxes to use that as gateway and set its IPv6 to 2601:d:8b80:c0::666 it works, I can ping ipv6.google.com from the lan box, etc.

but should the track IPv6 be first IP in the prefix?  And now if I look in dhcp6c_wan.conf, I see

interface em1 {
        send ia-na 0;   # request stateful address
        send ia-pd 0;   # request prefix delegation
request domain-name-servers;
request domain-name;
script "/var/etc/dhcp6c_wan_script.sh"; # we'd like some nameservers please
};
id-assoc na 0 { };
id-assoc pd 0 {
        prefix-interface em0 {
                sla-id 0;
                sla-len 0;
        };
};