I have a Verizon iPhone 5c. I want to switch to at&t go phone so i bought an At&t go phone Sim. My phone says no service. I haven't added any time to it yet because i don't want to spend money on something if its not going to work and i can return the Sim for a refund but i wont get the money back for the time card. But if i can get confirmation that service will come on when i add money/time i will add it. So am I doing something wrong or would i have to add time to my phone and Sim to get service?