Gotham City Impostors developer Monolith is working on a fix for a game-wrecking bug that is wiping players' stats.
However, some gamers in the ensuing thread claimed it happened to them even though they bought the full version first.
"Sorry about the inconvenience. We're doing everything we can to get this fixed as soon as possible!" promised Monolith's rep.
The multiplayer-focussed FPS scored a middling 6/10 when it launched on PC, PlayStation Network and Xbox Live Arcade earlier this month.
"Gotham City Impostors offers a minimum of substantive content - maps, in particular - and a maximum of unlockables that put unrealistic demands for grinding next to a 'buy now' button," read Eurogamer's Gotham City Impostors review.
"The gadget-enabled shooter at the heart of Gotham City Impostors is fun, smart and hard to dislike. But it's impossible to recommend."