We have observed that login is failing when user (UserIP) is on IPv6. Kibana log shows the following.
Does VIP AuthHub currently support IPv6?
Release : VIP AuthHub M8 release (ssp-1.0.2942) or M9 release (ssp-1.0.3170)
As of this KB article is written, currently VIP AuthHub doesn't support IPv6.
The plan is to support IPv6 and this task will start as a priority task in early 2023.