Discovering network does not work with CNC (TSN)

[nah1n]

Hello all,
I am trying to make a simple network with two IE4000 switches each has an end device and a single controller connected to a switch. I can manually ping all the devices (including controller pc) between each other. But when I am trying to discover topology it stays in (discovering topology state for an indefinite period of time).
I then canceled discovery and went to Devices (in the left menu) And I can see that they have found both of the switches, even if I have given the IP of only the switch which is directly connected to the controller. See the figure.
From here both switches can be sync, connect, and ping successfully. But when I run topology discovery it still does not work. 

Every time before running the topology discovery, I have cleaned the cache, deleted the device.

For testing the flow scheduling, even if the topology is not discovered, can I select these switches manually? Please help.

Thanks in advance.