My phone is a blackberry storm 2 9550 verizon phone, it's a gsm+cdma phone. I bought it on ebay, a brand new unused cell phone. The phone, after working for around 4 weeks straight, suddenly stopped working. The problem was mainly in searching for gsm, and sometimes sos would come up,. or the connection would even turn off by itself. And another problem that suddenly started occurring, was the fact that all the codes were being processed as calls. I tried the first and most obvious trouble shooting option, which was to remove the battery and put it back in, and remove the sim card and reinsert it, but none of that worked. I took it to digicel, which is the phone company that i'm with. they tried running a diagnostic test and from then on, the phone kept working off an on.I started seeing the edge come up every now and again. I took it to a guy who tried exchanging antennae, then doing an update, then flashing the phone, but none of that worked. I came to a conclusion. Probably verizon shut off the network on my phone for some reason, or I might be using an incorrect sim card. Can you tell me anything about gsm sim cards? I'm using one from digicel, should I be using a gsm sim card?