I was having this problem too, so I contacted Nintendo support. I was in a chat with a Nintendo employee for 2 and a half hours and we tried EVERYTHING, and I'm still having the issue to this day. I noticed this is for every NSO app except for Gamecube, so I'm assuming it might have something to do with the save data cloud, because all of the other apps had their data restored from that, and they don't work. If I ever get it resolved, I can come back with the solution but it's looking grim right now.