iPhone is being very erratic - texts arriving late, no notification, phone not ringing, one phone call came in, left voice mail, and when I walked outside to listen to the voice mail all remnants of that phone call had disappeared from the phone. I spent some time with ATT, then with Apple - we trouble shot, restored, futzed. Then it was suggested I go to ATT and get a new SIM card for this brand new phone. I went over there - they suggested I do nothing but wait until ATT actually finishes trying to fix my three local 3G towers, which are not performing adequately for the last few weeks. That would explain a lot of things, I think. So, I'll wait. In the meantime she had me change the network setting to E, the 2G network, which is working better in my nabe. I can switch it back to 3G when I'm in other parts of the city.