Active Directory authentication for RDP session to Ubuntu

If the Ubuntu box is active directory domain joined for user authentication, the domain users cannot authenticate without changes to the sssd.conf file.
sudo -i
cd /etc/sssd
nano sssd.conf
add 3 lines
case_sensitive = False
ad_gpo_access_control = enforcing
ad_gpo_map_remote_interactive = +xrdp-sesman

restart sssd
systemctl restart sssd

For domain user name use the full domain in this format.
user@nameof.domain