Alright, here's what's been going on:
LIVE is literally turning down any attempts I make of purchasing things on the store, from any of my consoles or my pc.
I did register my account as a US account, since that's where I was living and playing at the time. I have since then moved back to Brazil, and never had any problems using pay pal to pay for my stuff. Now, however, I've started having problems.
I've changed my region to Brazil. It says so on my console. It doesn't let me alter my billing address ON THE CONSOLE, the country's still the US. If i access my account from a pc, I can see my current and correct billing information.
It doesn't allow me to add a brazilian credit card.
I've gone so far as to make a new Microsoft account, registered in Brazil, and changed my Gamertag to this new account. Now I can't access or manage my account information.
Please help - I've run out of ideas of what could be wrong and I don't want to have to start a new account and new gamertag from scratch. Thanks!