My 3DS never has a problem reading cards. I recently I bought a game off Amazon (Story of Seasons: Trio of Towns if that makes a difference) and found that the DS wasn't detecting a game being inserted (the little icon where the game popped up stayed grey and couldnt be clicked on like there was no game cartridge)
I try it on a different 3DS and it was the same issue. No biggie, I send it back and get a replacement.
Only I've just tried the replacement copy (which is definately a new copy because I only just sent the old one back on the day this was delivered) and the same thing happened. Both copies of the game came in plastic and were unused, so I don't think it's damage from use, but it's not just me that that's weird, right?
This has to be a problem with the cards because it didn't work on both DS's, but is there something I can do to fix it? I don't want to have to send it back a second time only to have the same thing happen again