What exactly have you done ? You've reset the account's password, and then logged out and back in everywhere : If your Apple ID has been locked - Apple Support ?
If you have and it didn't fix it contact iTunes Support and see if they can/will re-enable it : https://www.apple.com/emea/support/itunes/contact.html
Creating a new account shouldn't delete content, but anything downloaded by your existing account is permanently tied to that account, so only that account can download updates to its apps etc.