Identity Safe

I have Identity Safe on 2 of my computers.  I just installed Norton 360 on a 3rd laptop, but I cannot get Identity Safe to install.  I enter my email address and password to sign in, but it returns me each time to enter my password.  Thinking I had the wrong password, I tried signing on with my other two computers with no problem.  Why can't I get past the initial sign-in with my new laptop?