Sims 3 question! PLEASE HELP!?

Ok. So a while back my Sims 3 account had a glitch from one of the custom contents I downloaded. Just recently I uninstalled my Sims and re installed it. On the account for sims 3 I used the same account name and password and I logged it in on the launcher too. I tried to download something but it wouldn't show up in the downloads in the launcher. I gave up on that and I made a new account thinking their was something wrong with the account and made a new one. I had the same problem with this new account too but because it wont let me put in my serial code because it was used by the other account I had. Please help I want to download custom content really bad.