AnyConnect profiles (and a few other things) are not automatically synchronized between ASAs in a failover pair. I'm not sure why Cisco has never fixed this but it's been a documented bug for quite some time.
You need to copy the files manually. They are small xml files and usually not too hard to copy.
If you've lost the primary unit altogether, you will need to recreate the profiles on the secondary active unit.
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...