I just got the iphone through a trade, it came with what I think is a knock off vapor case. It feels like metal. So when I got the phone I notice I kept going in to 1x or 2g whatever you wanna call it. So I went to verizon and they told me that the case could be the issue bc it had a slot for the sim card which makes it an at&t case. So I bought a verizon case and its been fine. So my question is does at&t cases not work for verizon iphones?