@stanwood I also live in Switzerland
I've got Fairphone 4 running 24.04-1.0 Beta 2 and my carrier is Yallo.

4G VoLTE is turned on but is unfortunately not working.

In the Ubuntu Touch Docs ( https://docs.ubports.com/en/latest/userguide/dailyuse/volte.html) one of the requrements is „Ubuntu Touch contains a VoLTE configuration for your carrier.„

Does anybody know how to create such a configuration?