AMZ1950

In the past month or so, I've gotten about 10 different warnings of new logins to my account from all over the world. I keep changing my password. Then I set up two-factor authorization, but still got told there had been a new login. How can that be and how can I stop this? Or do they only mean a "new login attempt," in which case if I have two-factor authorization, I would think I don't really care. But I'd welcome any thoughts about what's going on.