Seems like you are indeed affected by WARNING: Raspbian October 2021 release bullseye + unbound.
To fix this, try
- Edit file
/etc/resolvconf.conf
and comment out the last line which should read:
unbound_conf=/etc/unbound/unbound.conf.d/resolvconf_resolvers.conf
- Delete the unwanted unbound configuration file:
sudo rm /etc/unbound/unbound.conf.d/resolvconf_resolvers.conf
- Restart unbound:
sudo service unbound restart