Twitter issues?

[Raven]

So tonight my friend's twitter account got hacked and she asked me to get it back for her since I know more about things like that then she does.
I got it back and changed the password (with her permission) and told her the password and everything. I then registered her email with her twitter account and then made it so that she needed phone verification to sign in. While this was going down, she signed out of her account through her ipod.
Once everything was said and done, she tried signing back in. She is one the 4th gen ipod touch and she can't update to the ios 7.
Then the problem came: She tried signing in with her username and the password I provided her and a message popped up:
"EXISTING ACCOUNT" -This account already exists.
She cannot get access to her account with her ipod anymore. I don't know if it takes time to update or what. And she is on the SIGN IN screen, NOT the sign up one.

Help? She can only gain access to her account with her ipod, she has no access to a computer.
What do you guys mean by privacy settings? Is it privacy settings for Twitter or her iPod? Because Twitter's privacy settings have been left alone. The only thing we changed was that a verification code is sent to her phone now every time someone tries to log in onto her account for Twitter. And I had her delete her cookies for Safari from her ipod settings and that is it. Everything should still be in default.
PLEASE BE SPECIFIC.

[Light]

check your privecy settings.

[Miyake]

did your privacy setting disable other device's login