I'm posting for a friend. She has an iPhone SE with BOOST Mobile. She's been able to receive calls no problem, despite no sim card. She was in New Hampshire, and a friend suggested she clear files by holding down the home key and accessing old files (I don't understand this and have never done it), but since then she is unable to receive calls on her iPhone. in General> About> Network says 'Not Available'. Any help much appreciated. Thank you! --- Post Merged, Apr 22, 2018 --- note: She can receive texts via cellular, so is apparently still connected to some kind of network, even when no wifi connection. Thank you. --- Post Merged, Apr 22, 2018 --- Now it's working! I have no idea how, or how i fixed it. Thanks for all the great help here. Problem solved.