I purchased the international data roaming plan for $40, but the phone has failed to connect to connect to any cellular network whatsoever in the last 4 days in urban centers. It's infuriating, and caused me a number of serious hassles with being unable to text or contact others at important times. I've been working at this for hours. My phone can see all nearby networks in network settings, but fails to connect to them. Any help would be greatly appreciated.