NNID showing up on 3ds even though I'm on Pretendo

I went to play Mario Kart 7 and was surprised my original NNID showed up in game instead of my Prentendo account. I was able to play an entire race before a communication error occurred for the next race. My 3ds still thinks I’m using NNID even though Nimbus shows I’m on Prentedo. Any issue as to why this is? is there an update I need to do or anything?

Go to System Settings on your 3DS, then “Nintendo Network ID Settings”.
It’s possible you might not have linked a PNID yet.

(It’s normal for it to say Nintendo Network instead of Pretendo Network. Pretendo only patches the online servers, not the system stuff.)