How to find IP of DUO Radius Proxy

Hello, while configuring the Radius server in Fortinet SSL VPN, we have to put IP address of DUO Radius IP.

But I’m not sure how we can find it. Please guide. Screenshot attached

It is the IP address of your organization’s on-premises server where you installed the Duo Authentication Proxy. Only the person from your organization who installed the Duo proxy software can tell you the IP of the server where they installed it.