@Jeroen-van-Bussel of course you can work on automatic mode, the modem would scan through the whole PLMN list until it finds a network. This can take a while and I agree, it’s the only thing that makes sense for devices in non-static use cases.
I’ve set our modem to band 20-only.
I want to use auto-attach (at+cops=0) but it did not find a network
However, manual attach (with selecting Vodafone’s network) did work
Doing something else for about 30 minutes around the time @Kolja-Vornholt left the reply about searching the network.
Trying the search only gave me seemingly non-related info (“90104”),
But trying the auto-COPS suddenly did the trick and attached in no time.
NB-IoT roaming is available for the Global SIM of Deutsche Telekom.
The LPWA tariff “Europe Zone 1” currently provides NB-IoT roaming across 17 countries. These include:
Deutsche Telekom’s networks in Germany, The Netherlands, Austria, Czech Republic, Slovakia, Hungary, Greece, Poland and Croatia
Swisscom’s network in: Switzerland and Liechtenstein
Vodafone’s networks in Spain, Italy, Germany, The Netherlands and the United Kingdom
Telia’s networks in Sweden, Finland, Denmark and Norway
Telenet’s network and Orange’s network in Belgium
In European countries for which DT has no NB-IoT roaming agreements yet, multimode devices with the Global SIM can utilize 2G and 3G instead, and also LTE-M (currently in Germany, Austria, France, Belgium, Netherlands, Switzerland and Latvia).