Yes, previously, I had a Wii U console, which I brought to the store since its disc reader was broken. But I didn't know that I can link to only one console so I didn't unlink my previous Wii U. So I noticed it when i tried to do so with my new Wii U. It's something really bad because now I can't:
-Go to Miiverse
-Go To eShop
-Go play online
-Get the Mewtwo DLC for SSB.Wii U when it will came out (I am a huge Smash bros. fan so it's a very bad situation)
-etc.