Any experience with NB-IOT in Switzerland (using SIM7020E)

I have two breakout boards with a SIM7020E and a sim card (pilot plan) from Hologram.

There just seems to be no usable signal? I am located near Liestal. CSQ gives 0,0 and COPS=? finds two networks after searching for up to ten minutes. But no registration happens.

Does anybody have experience with Swisscom or Sunrise? Could it be that NB-IOT just does not work either with a Hologram sim card or at all?

Another strange thing is that Swisscom and Sunrise somehow claim to support NB-IOT but there is no useful information to be found!