The portugues SIM or. a travel SIM is only for mobile data, the rest will not vanish when you insert a second SIM to have mobile data? No contacts no Whatsapp no mails.,.I was in Canada and for sure did not want to use mobile data from my German SIM so added a travel SIM and could just use my phone when I had no Wifi connection.
And @mitodo86 experience clearly is not “normal”.
Edit: I’m still wondering if this is connected somehow to the not very useful 1&1 network? Its new and not very wide spread so maybe the world cant handle this? Also I know that 1&1 support lets say it nicely isnt the best…
@mitodo86 do you know which APN you use while in Germany?
Both: as the 1&1 network is not wide spread does your account use Telefonica when not covered, so maybe try the O2 APN?
It seems SIM de changes to Vodafone did this just happen while you traveled @mitodo86 and therefore there is no APN?