I would verify the configuration and setup of the kerberos.
I also found this information on the error being returned.
Hope this helps!
Long analysis on our side and nothing helped.
After installing version 2018.2.3, everything works fine (as it was in 10.5), so it was something wrong in 2018.2.1 and 2018.2.2 versions.
Thanks for following up on this discussion!