Same thing happening over here on PS5.
Changing to a different network (mobile hotspot) does fix it, but is not sustainable.
Suspecting a problem with IPv4 vs IPv6 as that's the only difference I was able to find between networks that do and don’t work.
There is a possible workaround - if you connect your Playstation to a different WiFi (e.g. Android Hotspot) it could work (did for me).
Very clunky though.