I am trying to use the Control app on a Samsung Galaxy Tab A running Android version 8.1.0. I am able to install the app, configure unattended access and connect to the tablet through the portal without issue. When the tablet is rebooted, the unattended access setting are removed.
Through my own troubleshooting, I enabled the storage permission for the Control app and rebooted. This time the unattended access settings stuck around. That being said, I had to manually open the app to regain a connection. Even with the storage permission enabled, the tablet took more than 5 minutes to become accessible in the portal.
I worked with Michael L on your support team. He was able to replicate the issue on his own tablet. He provided a case number to reference in this post, #11460745.
Customer support service by UserEcho