@PatLamb 

Hey

Not in the Omada range but I have had this issue recently with other vendors

If its the same issue for you it will affect Android 11 devices running the Feb/March 2021 security update.   Long story short the update brings WPA3 with backwards compatibility for WPA2, however, to achieve this in an enterprise setting it removes the ability to bypass certificate validation.  

Certificate validation bypass has always been a weakness of WPA2 so removing it in WPA3 didn't come as a suprise

Sadly this proved to be a real pain as its not possible to bypass this, ended up having to get a GoDaddy certificate and go down that route to speficially suit the Android devices.

The link below might explain this a bit more elegantly than I can

https://www.securew2.com/blog/android-11-server-certificate-validation-error-solution

@Philbert 

Thanks!