EA has taken FIFA 13's popular Ultimate Team mode offline while it deals with "recent trade pile and auction house complications".
Ultimate Team online gameplay, trading and store purchasing have been disabled, as have the web mobile applications.
Players have reported trade cards disappearing, sold cards getting stuck in their trade pile, and the inability to add bought cards to their team.
EA said: "FUT13 is temporarily down until further notice while we address the trade pile issue. This is to ensure that more users do not become affected and an optimal experience can be sustained in the future.
"We'll keep you updated as soon as we have additional information throughout the coming days. Other FIFA 13 online game modes will not be affected.
"Thanks for your patience and sorry for the inconvenience."