DICE are aware that some players are experiencing a problem where their in-game stats and experience are not being recognized towards their progression on Battlelog or in-game. We have also identified what can cause this problem to occur.
This issue only affects games in which a player uses the FAMAS weapon. In any game where the FAMAS is used there is a chance that player stats and experience will not be recognized after the game. We are temporarily recommending that players avoid using the FAMAS and spread the word to fellow players to avoid the problems this error can cause.
This advisory and problem are temporary and we expect to have them soon. Thank you for your patience.