yasamoka wroteI've read that (with some people), using proxy to access the Mexican Origin Store will make you unable to buy games from your own country's Origin Store. So keep that in mind and make sure you don't fall into that. You might want to check if the issue is valid.
AFAIK, using a proxy would be just as if you were in Mexico and bought the game, then returned to your own country. It might just be a bug that can be fixed by contacting support about the issue, that is if it is true.
i bought it yesterday for 25$ from the Mexican store
i will report if anything happens to my account