How to diagnose the operation of a terminal farm?

Question

Windows Server

Hello everyone, colleagues point me in the right direction. There is a terminal farm on windows server 2016, a broker, several terminal servers. There are problems related to the fact that: "hung sessions" appear on terminal servers, which are not removed by anything, except for restarting the server; terminal servers "fly out" from the farm, which leads to the fact that all users get only to it (this can be seen in the remote desktop service manager console).
The question is how to diagnose all this? Nothing significant in the events - there are no windows logs. How do you decide this or thoughts on where to start?