This happened to me with my new micro sd card. The weird thing is, I have A9LH, so the micro SD was working to the extent that A9LH would boot, but then on the menu none of the games would load and I'd get the error that the SD Card is not accessible. Its a 200GB Micro SD card, and I thought, shit, this card must not be compatible for some reason, I had formatted it correctly to fat32, but something was wrong. I was going to return the card when I decided to just format the card again, I opened the formatting program and deleted the entire partition, after that I formatted the card to fat32 again, literally changing nothing from the time I had tried before, and then for whatever reason my micro sd card loaded including all the games from my backup that I copied over that were not loading for whatever reason before. Point is, sometimes you just got reformat, even if you did nothing wrong.