I was just given a Verizon iPhone 5. It was my understanding that at the point of the iPhone 5, the iPhones either supported the bands for CDMA or GSM. I stuck the sim from my Unlocked iPhone 6 in it just for the heck of it, and it worked. For like 2 hours. Now it is saying no service. If I pop the sim out and back in or do a power cycle, it comes back up for like 30 seconds (with 3-4 bars, which is what my iPhone 6 gets), and then it goes to No Service. Any ideas what is going on?