Hi I updated my sd card filesystem to fat32, moved again the files to the card but when I try to start a game that is on sd card it says me: couldn't start the game. Why it happens?
You will need a micro SD card for your device. It should be formatted as FAT32 and MBR, not GPT (most micro SD cards will be formatted this way by default).
If your Switch won’t read your larger than 32GB micro SD card without a System Update, you can use guiformat on Windows to format it as FAT32 with an Allocation Unit Size of 32K (32768).
I fixed it. I didn't provided more information because it wasn't needed.
I just had to reinstall the games.
May be it has to do with the block of the game files.