I borrowed my friends micro sd card reader and put some games on my ds, a week later i did it again, but when it loaded up my micro sd folder, the folder froze. I tried to unplug it and replug it back in, but it said i needed to format my sd card. I tried to format my SD card but it wouldn't work... i plugged my sd card back into my ds and all the game that were already on it still worked... whats going on? is my SD card broken, or is it the microSD reader? can i fix this?