i recently bought a BB Storm2 9550 Verison, the dealer told me its unblocked and i confirmed its he also said it can be used on any GSM network in the world but when i inserted my sim card it could not be recognised and the network bar is reading sos.i took it to the network provider the told me Verison can not work on the network can any one help on this one.do i need to change the OS or something.