Why would you even want to use Netflix on your Xbox? That machine's for games, son, not silly "critically acclaimed" TV shows where you can't even set NPCs on fire to move the plot along. Still, if you absolutely must befoul the console with such things, know that Microsoft is looking into today's upsurge of sign-in problems. "Hey Xbox members, are you having trouble signing into the Netflix application?" reads the Xbox Live Status page. "We're aware of this issue, and we're already working hard to find a solution. We appreciate your patience in the meantime, and we'll update you on our progress in 30 minutes." Source - OXM
I have a netflix account on my TV, laptop, PS4, Xbox One and the Xbox One is fine? They're all working