2 step verification

I just got the new launcher and I saw that you could change the skin in the launcher and when I try to use my 2 step verification, it doesn't work so I knew that I forgot it and then I went to mojang to change it and what happened is I changed the 2 step verification to something that I would remember and then I log out because I thought that I would have to do that to change but when I logged in it was still the same.