Not if you're nicknaming. Only the first byte after the characters you want is FF. That's how trash bytes work. The game makes as few writes as possible.
In this case, it should erase the characters afterward with either FF or 00.
Hmmm... A blank save file.
Here's some things to try:
-Make sure there's no gunk on the cartridge's contacts
-Make sure the cartridge is all the way in the adapter.
--If it is, try pulling it out very slightly. Sometimes this helps on my NDS Backup Adapter Plus
-Make sure you have the latest software/drivers
--If that doesn't work, try a previous version or two if available
Don't worry, the multiple accounts thing is mainly so you can't avoid a ban. (So you're fine unless you get banned, but I'm sure that won't happen.)
Anyway, it's nice to have you here! Welcome Find__Tab!
It says met at level 47. Serebii says the max level for that route is 45. I don't know if that matters, but maybe that info will help the developers determine if this is in fact a bug.
http://serebii.net/pokedex-bw/location/591.shtml#black2
I ban LEGOanimal22 for respecting that power. Power that made us shut down a nuclear reactor, because a fight over 2 miles away started interfering. (Fortunately, the fight wasn't in the nuclear reactor.)
I ban LEGOanimal22 for using the avatar of a Darkrai. Darkrai gave my company a great deal of trouble, even after contracting amnesia. Before that, he tried to ruin the world. Twice.