Is the SD card recognized on a computer and is it formatted with FAT32? Make sure it is formatted and if you are absolutely sure it is go inot storage settings in settings and see if the SD card is recognized there. if it is, just click format sd card and then it should work fine. If not check the pins inside the sd card slot and see if they are all straight and aligned. If not then it would require soldering and a new sd card reader to fix it. If they are then i honestly have no clue what it would be. maybe @oldturkey03 or @mayer knows?