Okay so usually I use straight-talk's service plan on my iphone4 (at&t GSM). I have to unlock it in order to get the data and messages to work. well, I forgot to refill my plan in time, thus causing my service to be disconnected. I had to buy a new sim along with the new one month plan card. I found out that straighttalk quit offering at&t compatible sim cards AFTER i had already purchased it. BUT, the sim card is still "t-mobile or any unlocked GSM phone compatible". Well, my phone is saying "SIM Failure" and Im not getting any service or anything. Can someone help me to figure out how I can make this sim work in my iphone4 at&t GSM? I tried the usual unlockit.co.nz , after i unlock it, it says "sim failure" immediately. I have to get this to work. I dont have a cellphone and I put all my disposable income into this.