SAMEEEEEE!! like it jst doesnt wanna work

I found how to fix my problem,you must upgrade splatoon if you haven't already,then you can play.If it says that you can't upgrade the game remove the sd an it will install it.Then you're ready to go.Try,it worked for me

to solve it turn off your wiiu then turn it on again and it should work but if it doesn't work try it again

turn off pretendo in aroma and update using your nnid account '•'