mobile

Hello Guys, I have sony Xperia V, everything was fine until i was going to install cm12, i did a factory reset with erase internal memory too, then after i flashed the rom, everything went fine but i was unable to move or copy or store anything in and out of the internal memory, and none of my apps are able to read or write data into it, i tried reflash the rom and tried to flash the stock rom but the problem is still on,
What should i do, please help me!