Update: In what was originally believed to be an issue with Pokemon Sword and Shield it turns out that this issue is related to a problem with the Nintendo Switch OS itself. While many who play games on the Nintendo Switch wouldn't have come across this bug it's apparently well known in the homebrew and modding scene. User CTCaer explained it in a github issue thread as follows:

The bug is in Nintendo's exfat driver. It constantly changes folders/files even on reads. And because it never syncs properly, on a hang/force quit/force reboot/power off, the handles are lost and the files/folders become missing from the file allocation table. Because exFAT does not have a 2nd FAT like fat32, these file/folders cannot be recovered.

This is something that modders have come across but it just seems no commercial game has had this issue, or at least been as big a game as Pokemon. For now the best solution for people is to make sure that their SD cards are set up as fat32, if your SD card is exFAT then the best you can do is hope that you don't encounter this issue.

The original story is listed below.

Original Story: Several players are reporting that Pokemon Sword and Shield is somehow managing to delete other game's data. A Pokemon game having issues with save data isn't anything new, but this is a somewhat odd situation — it's reportedly deleting the save data of other games.

A submission on the /r/pokemon subreddit details the problem. Apparently, the game is locking up when attempting to do an autosave. Again, a bug like that isn't particularly noteworthy for any game. It's what happens afterwards that's interesting.

After what appears to be an attempted autosave, a message pops up regarding data on the Nintendo Switch console. Horrified players head back into the system's menu, only to find that games on their SD cards have had their data entirely erased.

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As problems go, this is a pretty bad one. What's causing it, and what can players do to fix it?

What's Causing Pokemon Sword and Shield to Delete Data (and How to Avoid It)

Unfortunately, the people who have suffered this problem haven't quite figured out the exact cause of this problem, other than the fact that it happened while they were playing Pokemon Sword and Shield. However, a look at multiple instances has identified several trends to keep in mind.

This issue primarily seems to be happening to people on the eShop version of the game.

Your SD card may be a factor in this problem; using a card that's formatted as FAT32 rather than exFAT may help.

While this issue was first thought to be linked to the auto-save feature there are also reports of it happening if autosave has been disabled

That's all we know for now. What's causing the issue still remains a mystery for the moment. This seems like some kind of pretty bad bug, so let's hope that it gets fixed sooner rather than later.

Have you experienced Pokemon Sword and Shield deleting the save data of other games? What do you think of the game so far? Let us know in the comments below!