Two Step Authentication yes? You have to re-authenticate, as you've said, every 30 days on each PC you log into. YOU KNOW THIS WHY AM I TELLING YOU?
I do, in fact, know this. I learn it the hard way just about every month I think.
Ha. Get some of the emergency codes and keep em in your wallet.
Good idea. I thought I did that but I just looked in my wallet and I didn't! I have my phone so I'm going to print those now and stow them in a pocket in my wallet so I can forget all about them!