http://www.gearbest.com/mobile-phone-parts/pp_328085.html?vip=1029640
this store sell 100% original and send all over the world. I recoment this site because is a regular store with warranties, and etc.
sometimes it happend, its a bug, when turning off wifi if you dont connect to mobile date, turn airplane mode on and off. I will unlock the bug. also check you mobile data config, make sure you have apn correct