Got my gateway card recently and followed the guide to set up emunand. Good so far. When I updated the emunand to the latest one available, gateway mode doesn't load up. Idk what I did wrong.
You probably updated past 9.5 and you're using a new 3ds console.
Use 3dnus or similar to download the .CIA files to update your emunand to 9.5
(Format emunand again in the gateway menu of course)
There are threads on how to do it if you search.