Prosafe GS728TP Radius doesn't work

Hi, 

I'm trying to configure a ProSafe GS728TP switch to use a radius server on a Windows Server 2019 to authenticate users on the network, but the switch can not connect to the radius server.

What I've done so far;

• Updated the firmware to the latest version
• Configured the Radius server settings in the switch to the Windows Server IP address
• Configured the Accounting server
• Set the port connected to the server as Active
• Set Port Authentication to Enabled
• Configured workstations through Group Policy to use Wired Network Policies (IEEE 802.3)
• The firewall is disabled on the server.

When i do my test from my client machine to authenticate a user, i don't see any connection from the switch to the radius server. 

I tried after that to authenticate the Admin user of the switch using 'Radius - Local - None' options, and then i noticed that the switch was able to request my radius server ! and when i disable this options 'Radius - Local - None' the switch don't send any request to the radius server ? 

Can you please help, on how can i configure the radius on my switch without activate the 'Radius - Local - None' ?