External connections can not get reconnected cleanly

I have a complex setup, I use a NetworkServerSimple for listening to UDP port and NetworkServer listens to WebSocket (TCP) port.
Then I add connections of the UDP simple server to NetworkServer and remove them at disconnect time so web and mobile users can play together.

Now if a client connects to server and then disconnects my game stops to work for the client after 1-2 minutes. What happens is that RPCs are not sent to the client from scene objects after 1-2 minutes. I guess list of...

External connections can not get reconnected cleanly