Hi people I have just brought a sf on e bay, it's in great condition...I have unlocked it using a code, all was fine until yesterday when it has started showing a black screen with the green Android on, sometimes it loads back up but today I had to take the battery out and plug it through the usb which worked.......I haven't done anything to the software......I'm worried it will just stick at that...it only came on Thursday, has anyone got any ideas of what it could be? Should I contact the seller etc, any help would be much apreciated, thanks Chris