On the proxy events section you see the following error
kid1| ERROR: Negotiate Authentication validating user. Result: {result=BH, notes={message: gss_accept_sec_context() failed: Unspecified GSS failure. Minor code may provide more information. Clock skew too great; }}
This error means you have a time difference between your Active Directory and the Artica Proxy
To make sure this error did not occurs, enable the NTP service on your Active Directory server and set your Artica client as NTP client of your Active Directory.
You can also set your Artica server as NTP server and set your Active Directory server as NTP Client
Or just change the time of your Artica server in order to reflect with few seconds differences your Active Directory time.