I bought a new Sony Ericsson mobile K530i 3 days back. I checked its working with my dad's airtel sim, and it worked well. 2 days ago, I bought my own sim from Airtel. It was activated all fine, but when I returned home, I found that it did not receive a tower. I waited for a day just to make sure, and it showed "Emergency Calls only" at some times, and "No network connections" at other times. Other airtel mobiles...