Why does the RDP session fall off?

Question

Windows Server

There are two servers running Win 2008 R2, 1C is running on one, the DNS and DHCP roles are configured on the second.
There is no domain, everything is in the working group.
There are approximately 25 clients under Win10

. Several (approximately 5) have a problem: if you collapse the RDP session, then after 5 minutes it breaks and when deployed, the connection is restored.

What could be the problem?

Answer 1

check their network... if there are any interruptions in the connection
sleep modes on the PC... and all that

Answer 2

There are no problems with the network and there is no domain, check the local policies on the terminal server and look towards the session behavior settings. Perhaps there are some settings, because the minimized session is not an active session.