Nintendo switch sd card problem?

Last week my old SanDisk SD card (32GB) broke in the reader when I was repairing my Switch. Today I put in a new 512GB SD card, also from SanDisk. The problem is that the Switch settings say the SD card only has 466GB of space left, and there's nothing on the SD card except Animal Crossing: New Horizons. Does anyone know what the problem is? If I theoretically fill the SD card to over 466GB, what would happen? I've done the math and with ~32GB + the ~5GB from ACNH with the 466, that would be ~505. Is the console experiencing some kind of display error or is it getting confused with the data?