I had a strange behavior this week while I was travelling from Germany to the UK and back.
My two SIMs are from O2 and Vodafone. Both worked fine when I left Germany.
I put the phone in flight mode for the flight and switched flight mode off once we had arrived in London. The phone didn’t connect to any network automatically.
I was able to manually connect to O2 UK and use the mobile data. Whenever I tried to call a number it stated „mobile network not available“. And I was not reachable, callers got the message that I was „temporarily not availabe“.
With Vodafone I was not able to connect to a network at all. The manual search option immediately showed an network error. When I tried to select a the option for the preferred network I got the message „registered to network“.
I tried several things: reboot the phone, switched the phone off, I also switched the SIM cards, switched on and off roaming. Nothing helped. I also called O2 to check that with my contract everything was fine.
When I was back in Germany both SIMS worked again flawlessly. There I also received the SMS with the roaming info.
This was my first trip abroad with Android 7. My last trip to Ireland in August was with Android 6 – everything worked back then, for both SIMs.
Are there any similar experiences or tipps for the next time? This was really annoying.