Sophos Switch and Microsoft NPS (RADIUS)


I am trying to implement 802.1x on Sophos switch with Microsoft NPS server. After configuring all settings on both sides (IP addresses, shared secret etc..) there is no logs from Sophos switch in event log on NPS server. I checked on firewall that switch is sending requests to NPS. If I remove Sophos switch from clients in NPS, I get message that NPS received requests from unknown client (switch). Log settings display all events since I have 802.1x enabled on other switches and Access points.

Are there any special considerations adding Sophos switch to NPS (manufacturer)?

And are there any special VSA codes used for dynamic VLAN assignment?