@Digitec, expect such a statement here as well.
I bought the 8T and am trying to get 5G working on the (pretty well developed) Sunrise network. Provider support could only confirm that 5G is enabled and can be received well at my location. The phone is set to 5G, and even with the "advanced phone settings" (accessible by dialling *#*#4636#*#*) I had no success.
As mentioned by @Da78270, Digitec sells this phone as a 5G device in Switzerland. Then Digitec should also specify how to use it in Switzerland (on the only three possible networks). Simply switching it on (as one would expect) is not possible.

I think that would be more of a question for your provider. If a device supports 5G, why shouldn't it work?