if you bought with paypal the username and password should be on the paypal receipt

Agreed, If not do the usual, Support ticket. But be patient. When you purchased it says "put username - password" thats the UN/PW you need to use. If not, Nobody but Admins can help. Virus, Tox or Jim as its the Auth Server.

When you re-sub again, You just enter the same username, leave PW blank.
 
When you first run the Login Updater you will be presented with the above window. Simply enter your username, password and select the product your purchased and press login.

Choose the right one that might be a problem too

When you have successfully authenticated you will see a popup showing the latest version and when your hack expires.

Press the "Download Full Hack" button to get a copy of the hack, ignore the Download DLL option.