Yesterday, I asked my mom to clean my copy of Mario Kart 7 and ACNL, and, maybe it's just because I haven't cleaned the game card slot in either of my 3dses (I have a small black one from 2012 and a NEW3dsxl from 2015), but my devices don't read either card (my black one read ACNL once, though). I kept inserting and re-inserting my games and they didn't read. Although, I don't know how my mom cleaned them, and I was eating popcorn, which has some oils. Any help/suggestions?
I've had the same happen to me with some Switch games and I honestly have no idea why it happened... it wouldn't read a cartridge for no reason despite being able to read other games... then I left it for some time and tried again, pushed it a bit more - it worked and doesn't have this issue now.
Have you tried waiting a bit and retrying? Or restarting the system? I think you need to try other cartridges if you have them and if not - maybe go to Gamestop and ask if they can help you. : p
