I've been having some trouble with my iPhone over the past couple of days. It has been randomly slowing down, freezing up, and lately I've had to do a couple of hard restores. Tonight I was out and noticed that it said that no SIM card was installed. I use Verizon so, to my knowledge, there shouldn't be a SIM card in there. After a few hours of trying to hard restore it, it finally came back on but only for 5 minutes before going black again for good. Nothing I do can make it boot back up. When I plug it in, iTunes immediately tells me that the phone is in recovery mode. I have tried to boot it up regularly and I believe that I have tried it in DFU mode a few times. It still goes about 70% of the way before giving me the error message that I mentioned in the title. I have tried restarting, changing USB ports, everything. There's no anti-virus program installed on my computer. Does anyone have any recommendations? I would really appreciate it!