BLU Life One 4G LTE Smartphone - GSM Unlocked - 8GB + 1GB RAM - Black 4G LTE, Unlocked Dual Sim Phone, Android 4.4 KitKat with Immediate Upgrade to Lollipop 8GB internal with 1GB RAM, Qualcomm Snapdragon 410, 1.2GHz Quad-Core, 64-Bit architecture and Adreno 306 GPU 5.0" HD 720p Display; 13MP Sony IMX 135 Sensor Camera with LED Flash, 5MP Front Camera 4G LTE,(4/7/17),4G HSPA+ (850/1700/1900/2100). GSM Quad Band: US Compatibility Nationwide on all GSM Networks including AT&T, T-Mobile, Cricket, MetroPCS, Straight Talk and others Unlocked, and compatible World-Wide including Brazil, Mexico, Colombia, Venezuela, and other countries.Kindly refer the user manual attached below for troubleshooting steps and instructions