Force user authentication in sophos firewall.

Good morning everyone,

We are using a Sophos XGS firewall in our company, with some allow rules that are specific to certain Active Directory (AD) users. The firewall is fully integrated with our Active Directory, and we have STAS running on our domain controllers.

Most of the time, the user-based rules work correctly. However, occasionally, some users cannot reach network resources that should be allowed by the firewall policy. When checking the Live Users section in the firewall, these users do not appear as authenticated, even though they are connected to the company network and properly recognized by the domain.

This issue typically resolves itself after 15-20 minutes, after which the users can access the resources again.

I would like to understand:

1. Is there a way to force user authentication on the firewall manually to avoid waiting for automatic resolution?
2. Are there any recommended troubleshooting steps to identify why the authentication is sometimes delayed?

Any advice or best practices would be greatly appreciated.

Thanks in advance!