Windows Machines not Validating Cert

[FreeRAD]

I'm using EAP-TTLS. When generating the production certs I know it says in
the readme file that all client machines need to have the root CA installed
for it to work, but that doesn't seem to be the case in my setup. If I
connect from a windows 11 machine I get a notification asking if I am happy
with the certificate information for the server that I am connecting to,
but I haven't got the root CA cert installed on my machine. I then just
accept the notification and it allows me to connect. Even after installing
it nothing really changed.

Would this indicate that something is set up wrong with the RADIUS server?
The debug logs confirm that a TLS handshake is complete.

Many thanks!