DrkrZen because you bought the card last year. the card was manufactured last year, it is too old to work on the latest 3ds firmware, so your card was blocked by your 3ds version, even your card is the version C, actually there are indeed some version C card can not be updated to support the 3ds new firmware. Currently the latest version of r4i gold 3ds is the rts version. I am afraid you can only use your card on your dsi for now and need to buy a new card for your 3ds. PM me if you plan to buy a new one, will send you a discount for the new card.