FIFA 13's Ultimate Team mode has been offline for the better part of the day due to bugs that EA discovered with the mode's trade and auction house features which caused players to potentially lose their trade cards.
Players complained that their trade cards disappeared, and sold cards would get stuck in their trade pile. Additionally, some players were unable to transfer purchased cards to their teams, rendering them more or less useless. The bugs have since been fixed.
"#FUT is back up on console, Web App and on the iPhone app. Thanks for your patience," said EA on the official FIFA twitter account, hopefully dealing with the matter once and for all.
With any luck, players won't have to lose any more of their cards.
FIFA 13 has been available on the Xbox 360, PS3 and PC since late October, 2012. It is one of EA's most successful games to date, selling 7.4 million copies since its release.