2 times now my new (6 weeks old) iphone 6 has displayed the message 'no sim' card and then can't connect to internet and I can't make calls. The software is up to date, and I have not done anything with the sim card. Rebooting the phone and turning on/off airplane mode doesn't help. After a 1/2 hr or so, it comes alive again. What's happening, how can I prevent this?
