How to fix error 022-2634 or unlink NNIDs without formatting

What you wanna do is unlink your NNID locally so you can relink it manually, which will also relink them in Nintendo's servers. Plailect already wrote a guide on GodMode9 for unlinking the local NNID:

https://3ds-guide.b4k.co/troubleshooting#removing-an-nnid-without-formatting-your-device

After you finish, you can either re-link your NNID normally again (this time you won't get the error anymore), create a new one or just not use a NNID at all. Whatever floats your boat.
(Personally I don't think there's much of a reason to have a NNID (especially a legit one, at least make a new one) in a hacked system and it'll just make you look more suspicious, now that we know they're banning people).

-----------------------------------------------------------------------------------------
FOR PEOPLE WHO JUST WANT TO UNLINK THEIR NNID FOR WHATEVER OTHER REASON UNRELATED TO THE ERROR

>The dirty way
Just follow the instructions above, but MAKE SURE to keep a backup of it (it should stay on your NAND with an "1" in its from after you follow the guide above, don't delete it and you can copy it to 0:/gm9out too just in case.
	"Why is it dirty?", you may ask. Although it just werks, your NNID will still be linked on Nintendo's servers, so it'll at least look fishy on their side (especially if you link another). Re-linking later will need both the original file and the NAND it originated from (if you lose either, you gotta call Nintendo and make up some bs like your 3DS got stolen or something). No idea if this had any influence on the recent banwave or ever caused any problem though.

>The clean™, legit™ way but that takes some time
1. Backup your NAND.
		>Detailed instructions here: https://3ds-guide.b4k.co/godmode9-usage#creating-a-nand-backup
		>Make sure to also have an up-to-date GodMode9 install (scroll up on the link above to get it)
2. Rename your "Nintendo 3DS" folder to something else like "Nintendo 3DS2".
		>This is because the official format wipes the folder contents. Do not skip this.
3. Boot your system (your CIAs and theme should be missing from the renaming, this is expected).
4. Go to System Settings and do a System Format. It'll connect to the internet to unlink your NNID.
5. Restore your NAND backup.
		>Detailed instructions here: https://3ds-guide.b4k.co/godmode9-usage#restoring-a-nand-backup
6. Delete the new "Nintendo 3DS" folder that has been created, rename the old one back to "Nintendo 3DS".

At this point, you've basically triggered the error 022-2634 on purpose, meaning your NNID is unlinked on Nintendo's servers. Now you gotta unlink it locally, which is trivial. Follow the instructions on the beginning of this paste to "fix" it, and then you're 100% divorced from ANY NNID, both locally and on their servers, and can do whatever the fuck you want.

-----------------------------------------------------------------------------------------

Old guide that still uses Decrypt9 and accounts for A9LH/menuhax+emunand if you want it for whatever reason (fucking dinosaurs): https://pastebin.com/Ji5tdKvL